-
question_answer1)
If the body is moving in a circle of radius r with a constant speed \[v\], its angular velocity is [CPMT 1975; RPET 1999]
A)
\[{{v}^{2}}/r\] done
clear
B)
\[vr\] done
clear
C)
\[v/r\] done
clear
D)
\[r/v\] done
clear
View Solution play_arrow
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question_answer2)
Two racing cars of masses \[{{m}_{1}}\] and \[{{m}_{2}}\] are moving in circles of radii \[{{r}_{1}}\] and \[{{r}_{2}}\] respectively. Their speeds are such that each makes a complete circle in the same duration of time \[t\]. The ratio of the angular speed of the first to the second car is [NCERT 1980; MNR 1995; CBSE PMT 1999; UPSEAT 2000]
A)
\[{{m}_{1}}:{{m}_{2}}\] done
clear
B)
\[{{r}_{1}}:{{r}_{2}}\] done
clear
C)
1 : 1 done
clear
D)
\[{{m}_{1}}{{r}_{1}}:{{m}_{2}}{{r}_{2}}\] done
clear
View Solution play_arrow
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question_answer3)
A cyclist turns around a curve at 15 miles/hour. If he turns at double the speed, the tendency to overturn is [CPMT 1974; AFMC 2003]
A)
Doubled done
clear
B)
Quadrupled done
clear
C)
Halved done
clear
D)
Unchanged done
clear
View Solution play_arrow
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question_answer4)
A body of mass \[m\] is moving in a circle of radius \[r\] with a constant speed \[v\]. The force on the body is \[\frac{m{{v}^{2}}}{r}\] and is directed towards the centre. What is the work done by this force in moving the body over half the circumference of the circle [NCERT 1977; RPET 1999]
A)
\[\frac{m{{v}^{2}}}{r}\times \pi r\] done
clear
B)
Zero done
clear
C)
\[\frac{m{{v}^{2}}}{{{r}^{2}}}\] done
clear
D)
\[\frac{\pi {{r}^{2}}}{m{{v}^{2}}}\] done
clear
View Solution play_arrow
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question_answer5)
If a particle moves in a circle describing equal angles in equal times, its velocity vector [CPMT 1972, 74; JIPMER 1997]
A)
Remains constant done
clear
B)
Changes in magnitude done
clear
C)
Changes in direction done
clear
D)
Changes both in magnitude and direction done
clear
View Solution play_arrow
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question_answer6)
A stone of mass \[m\] is tied to a string of length \[l\] and rotated in a circle with a constant speed \[v\]. If the string is released, the stone flies [NCERT 1977]
A)
Radially outward done
clear
B)
Radially inward done
clear
C)
Tangentially outward done
clear
D)
With an acceleration \[\frac{m{{v}^{2}}}{l}\] done
clear
View Solution play_arrow
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question_answer7)
A body is moving in a circular path with a constant speed. It has [CPMT 1972]
A)
A constant velocity done
clear
B)
A constant acceleration done
clear
C)
An acceleration of constant magnitude done
clear
D)
An acceleration which varies with time done
clear
View Solution play_arrow
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question_answer8)
A motor cyclist going round in a circular track at constant speed has [NCERT 1975]
A)
Constant linear velocity done
clear
B)
Constant acceleration done
clear
C)
Constant angular velocity done
clear
D)
Constant force done
clear
View Solution play_arrow
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question_answer9)
A particle \[P\] is moving in a circle of radius \['a'\] with a uniform speed \[v\]. \[C\] is the centre of the circle and \[AB\] is a diameter. When passing through B the angular velocity of \[P\] about \[A\] and \[C\] are in the ratio [NCERT 1982]
A)
1 : 1 done
clear
B)
1 : 2 done
clear
C)
2 : 1 done
clear
D)
4 : 1 done
clear
View Solution play_arrow
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question_answer10)
A car moving on a horizontal road may be thrown out of the road in taking a turn [NCERT 1983]
A)
By the gravitational force done
clear
B)
Due to lack of sufficient centripetal force done
clear
C)
Due to rolling frictional force between tyre and road done
clear
D)
Due to the reaction of the ground done
clear
View Solution play_arrow
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question_answer11)
Two particles of equal masses are revolving in circular paths of radii \[{{r}_{1}}\] and \[{{r}_{2}}\] respectively with the same speed. The ratio of their centripetal forces is [NCERT 1984]
A)
\[\frac{{{r}_{2}}}{{{r}_{1}}}\] done
clear
B)
\[\sqrt{\frac{{{r}_{2}}}{{{r}_{1}}}}\] done
clear
C)
\[{{\left( \frac{{{r}_{1}}}{{{r}_{2}}} \right)}^{2}}\] done
clear
D)
\[{{\left( \frac{{{r}_{2}}}{{{r}_{1}}} \right)}^{2}}\] done
clear
View Solution play_arrow
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question_answer12)
A particle moves with constant angular velocity in a circle. During the motion its
A)
Energy is conserved done
clear
B)
Momentum is conserved done
clear
C)
Energy and momentum both are conserved done
clear
D)
None of the above is conserved done
clear
View Solution play_arrow
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question_answer13)
A stone tied to a string is rotated in a circle. If the string is cut, the stone flies away from the circle because
A)
A centrifugal force acts on the stone done
clear
B)
A centripetal force acts on the stone done
clear
C)
Of its inertia done
clear
D)
Reaction of the centripetal force done
clear
View Solution play_arrow
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question_answer14)
A body is revolving with a constant speed along a circle. If its direction of motion is reversed but the speed remains the same, then which of the following statement is true
A)
The centripetal force will not suffer any change in magnitude done
clear
B)
The centripetal force will have its direction reversed done
clear
C)
The centripetal force will not suffer any change in direction done
clear
D)
The centripetal force would be doubled done
clear
View Solution play_arrow
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question_answer15)
When a body moves with a constant speed along a circle [CBSE PMT 1994; Orissa PMT 2004]
A)
No work is done on it done
clear
B)
No acceleration is produced in the body done
clear
C)
No force acts on the body done
clear
D)
Its velocity remains constant done
clear
View Solution play_arrow
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question_answer16)
A body of mass \[m\] moves in a circular path with uniform angular velocity. The motion of the body has constant [MP PET 2003]
A)
Acceleration done
clear
B)
Velocity done
clear
C)
Momentum done
clear
D)
Kinetic energy done
clear
View Solution play_arrow
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question_answer17)
On a railway curve, the outside rail is laid higher than the inside one so that resultant force exerted on the wheels of the rail car by the tops of the rails will
A)
Have a horizontal inward component done
clear
B)
Be vertical done
clear
C)
Equilibriate the centripetal force done
clear
D)
Be decreased done
clear
View Solution play_arrow
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question_answer18)
If the overbridge is concave instead of being convex, the thrust on the road at the lowest position will be
A)
\[mg+\frac{m{{v}^{2}}}{r}\] done
clear
B)
\[mg-\frac{m{{v}^{2}}}{r}\] done
clear
C)
\[\frac{{{m}^{2}}{{v}^{2}}g}{r}\] done
clear
D)
\[\frac{{{v}^{2}}g}{r}\] done
clear
View Solution play_arrow
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question_answer19)
A cyclist taking turn bends inwards while a car passenger taking same turn is thrown outwards. The reason is [NCERT 1972; CPMT 1974]
A)
Car is heavier than cycle done
clear
B)
Car has four wheels while cycle has only two done
clear
C)
Difference in the speed of the two done
clear
D)
Cyclist has to counteract the centrifugal force while in the case of car only the passenger is thrown by this force done
clear
View Solution play_arrow
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question_answer20)
A car sometimes overturns while taking a turn. When it overturns, it is [AFMC 1988; MP PMT 2003]
A)
The inner wheel which leaves the ground first done
clear
B)
The outer wheel which leaves the ground first done
clear
C)
Both the wheels leave the ground simultaneously done
clear
D)
Either wheel leaves the ground first done
clear
View Solution play_arrow
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question_answer21)
A tachometer is a device to measure [DPMT 1999]
A)
Gravitational pull done
clear
B)
Speed of rotation done
clear
C)
Surface tension done
clear
D)
Tension in a spring done
clear
View Solution play_arrow
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question_answer22)
Two bodies of mass 10 kg and 5 kg moving in concentric orbits of radii \[R\] and \[r\] such that their periods are the same. Then the ratio between their centripetal acceleration is [CBSE PMT 2001]
A)
\[R/r\] done
clear
B)
\[r/R\] done
clear
C)
\[{{R}^{2}}/{{r}^{2}}\] done
clear
D)
\[{{r}^{2}}/{{R}^{2}}\] done
clear
View Solution play_arrow
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question_answer23)
The ratio of angular speeds of minute hand and hour hand of a watch is [MH CET 2002]
A)
1 : 12 done
clear
B)
6 : 1 done
clear
C)
12 : 1 done
clear
D)
1 : 6 done
clear
View Solution play_arrow
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question_answer24)
A car travels north with a uniform velocity. It goes over a piece of mud which sticks to the tyre. The particles of the mud, as it leaves the ground are thrown
A)
Vertically upwards done
clear
B)
Vertically inwards done
clear
C)
Towards north done
clear
D)
Towards south done
clear
View Solution play_arrow
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question_answer25)
An aircraft executes a horizontal loop with a speed of 150 m/s with its, wings banked at an angle of \[{{12}^{o}}\]. The radius of the loop is \[(g=10\,\,m/{{s}^{2}})\] [Pb. PET 2001]
A)
10.6 km done
clear
B)
9.6 km done
clear
C)
7.4 km done
clear
D)
5.8 km done
clear
View Solution play_arrow
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question_answer26)
A particle is moving in a horizontal circle with constant speed. It has constant [MP PMT 1987; AFMC 1993; CPMT 1997; MP PET 2000]
A)
Velocity done
clear
B)
Acceleration done
clear
C)
Kinetic energy done
clear
D)
Displacement done
clear
View Solution play_arrow
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question_answer27)
A motor cyclist moving with a velocity of 72 km/hour on a flat road takes a turn on the road at a point where the radius of curvature of the road is 20 meters. The acceleration due to gravity is 10 m/sec2. In order to avoid skidding, he must not bend with respect to the vertical plane by an angle greater than [CPMT 1986]
A)
\[\theta ={{\tan }^{-1}}6\] done
clear
B)
\[\theta ={{\tan }^{-1}}2\] done
clear
C)
\[\theta ={{\tan }^{-1}}25.92\] done
clear
D)
\[\theta ={{\tan }^{-1}}4\] done
clear
View Solution play_arrow
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question_answer28)
A train is moving towards north. At one place it turns towards north-east, here we observe that [AIIMS 1980]
A)
The radius of curvature of outer rail will be greater than that of the inner rail done
clear
B)
The radius of the inner rail will be greater than that of the outer rail done
clear
C)
The radius of curvature of one of the rails will be greater done
clear
D)
The radius of curvature of the outer and inner rails will be the same done
clear
View Solution play_arrow
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question_answer29)
The angular speed of a fly wheel making 120 revolutions/minute is [CBSE PMT 1995; AFMC 2002]
A)
\[2\pi \,\,rad/s\] done
clear
B)
\[4{{\pi }^{2}}\,\,rad/s\] done
clear
C)
\[\pi \,\,rad/s\] done
clear
D)
\[4\pi \,\,rad/s\] done
clear
View Solution play_arrow
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question_answer30)
A particle is moving on a circular path with constant speed, then its acceleration will be [RPET 2003]
A)
Zero done
clear
B)
External radial acceleration done
clear
C)
Internal radial acceleration done
clear
D)
Constant acceleration done
clear
View Solution play_arrow
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question_answer31)
A car is moving on a circular path and takes a turn. If \[{{R}_{1}}\] and \[{{R}_{2}}\] be the reactions on the inner and outer wheels respectively, then [MH CET (Med.) 2001]
A)
\[{{R}_{1}}={{R}_{2}}\] done
clear
B)
\[{{R}_{1}}<{{R}_{2}}\] done
clear
C)
\[{{R}_{1}}>{{R}_{2}}\] done
clear
D)
\[{{R}_{1}}\ge {{R}_{2}}\] done
clear
View Solution play_arrow
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question_answer32)
A mass of 100 gm is tied to one end of a string 2 m long. The body is revolving in a horizontal circle making a maximum of 200 revolutions per min. The other end of the string is fixed at the centre of the circle of revolution. The maximum tension that the string can bear is (approximately) [MP PET 1993]
A)
8.76 N done
clear
B)
8.94 N done
clear
C)
89.42 N done
clear
D)
87.64 N done
clear
View Solution play_arrow
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question_answer33)
A road is 10 m wide. Its radius of curvature is 50 m. The outer edge is above the lower edge by a distance of 1.5 m. This road is most suited for the velocity
A)
2.5 m/sec done
clear
B)
4.5 m/sec done
clear
C)
6.5 m/sec done
clear
D)
8.5 m/sec done
clear
View Solution play_arrow
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question_answer34)
Certain neutron stars are believed to be rotating at about \[1\,rev/\sec \]. If such a star has a radius of 20 km, the acceleration of an object on the equator of the star will be [NCERT 1982]
A)
\[20\times {{10}^{8}}m/{{\sec }^{2}}\] done
clear
B)
\[8\times {{10}^{5}}m/{{\sec }^{2}}\] done
clear
C)
\[120\times {{10}^{5}}m/{{\sec }^{2}}\] done
clear
D)
\[4\times {{10}^{8}}m/{{\sec }^{2}}\] done
clear
View Solution play_arrow
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question_answer35)
A particle revolves round a circular path. The acceleration of the particle is [MNR 1986; UPSEAT 1999]
A)
Along the circumference of the circle done
clear
B)
Along the tangent done
clear
C)
Along the radius done
clear
D)
Zero done
clear
View Solution play_arrow
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question_answer36)
The length of second's hand in a watch is 1 cm. The change in velocity of its tip in 15 seconds is [MP PMT 1987, 2003]
A)
Zero done
clear
B)
\[\frac{\pi }{30\sqrt{2}}cm/\sec \] done
clear
C)
\[\frac{\pi }{30}cm/\sec \] done
clear
D)
\[\frac{\pi \sqrt{2}}{30}cm/\sec \] done
clear
View Solution play_arrow
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question_answer37)
A particle moves in a circle of radius 25 cm at two revolutions per second. The acceleration of the particle in \[m/{{s}^{2}}\] is [MNR 1991; UPSEAT 2000; DPMT 1999; RPET 2003; Pb. PET 2004]
A)
\[{{\pi }^{2}}\] done
clear
B)
\[8{{\pi }^{2}}\] done
clear
C)
\[4{{\pi }^{2}}\] done
clear
D)
\[2{{\pi }^{2}}\] done
clear
View Solution play_arrow
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question_answer38)
An electric fan has blades of length 30 cm as measured from the axis of rotation. If the fan is rotating at 1200 r.p.m. The acceleration of a point on the tip of the blade is about [CBSE PMT 1990]
A)
1600 \[m/{{\sec }^{2}}\] done
clear
B)
4740 \[m/{{\sec }^{2}}\] done
clear
C)
2370 \[m/{{\sec }^{2}}\] done
clear
D)
5055 \[m/{{\sec }^{2}}\] done
clear
View Solution play_arrow
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question_answer39)
The force required to keep a body in uniform circular motion is [EAMCET 1982; AFMC 2003]
A)
Centripetal force done
clear
B)
Centrifugal force done
clear
C)
Resistance done
clear
D)
None of the above done
clear
View Solution play_arrow
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question_answer40)
Cream gets separated out of milk when it is churned, it is due to [EAMCET 1981]
A)
Gravitational force done
clear
B)
Centripetal force done
clear
C)
Centrifugal force done
clear
D)
Frictional force done
clear
View Solution play_arrow
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question_answer41)
A particle of mass \[m\] is executing uniform circular motion on a path of radius \[r\]. If \[p\] is the magnitude of its linear momentum. The radial force acting on the particle is [MP PET 1994]
A)
\[pmr\] done
clear
B)
\[\frac{rm}{p}\] done
clear
C)
\[\frac{m{{p}^{2}}}{r}\] done
clear
D)
\[\frac{{{p}^{2}}}{rm}\] done
clear
View Solution play_arrow
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question_answer42)
A particle moves in a circular orbit under the action of a central attractive force inversely proportional to the distance \['r'\]. The speed of the particle is [CBSE PMT 1995]
A)
Proportional to \[{{r}^{2}}\] done
clear
B)
Independent of \[r\] done
clear
C)
Proportional to \[r\] done
clear
D)
Proportional to \[1/r\] done
clear
View Solution play_arrow
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question_answer43)
Two masses \[M\] and \[m\] are attached to a vertical axis by weightless threads of combined length \[l\]. They are set in rotational motion in a horizontal plane about this axis with constant angular velocity \[\omega \]. If the tensions in the threads are the same during motion, the distance of \[M\] from the axis is [MP PET 1995]
A)
\[\frac{Ml}{M+m}\] done
clear
B)
\[\frac{ml}{M+m}\] done
clear
C)
\[\frac{M+m}{M}l\] done
clear
D)
\[\frac{M+m}{m}l\] done
clear
View Solution play_arrow
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question_answer44)
A boy on a cycle pedals around a circle of 20 metres radius at a speed of \[20\,metres/\sec .\] The combined mass of the boy and the cycle is 90 kg. The angle that the cycle makes with the vertical so that it may not fall is \[(g=9.8\,m/{{\sec }^{2}})\] [MP PMT 1995]
A)
\[{{60.25}^{o}}\] done
clear
B)
\[{{63.90}^{o}}\] done
clear
C)
\[{{26.12}^{o}}\] done
clear
D)
\[{{30.00}^{o}}\] done
clear
View Solution play_arrow
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question_answer45)
The average acceleration vector for a particle having a uniform circular motion is [Kurukshetra CEE 1996]
A)
A constant vector of magnitude \[\frac{{{v}^{2}}}{r}\] done
clear
B)
A vector of magnitude \[\frac{{{v}^{2}}}{r}\] directed normal to the plane of the given uniform circular motion done
clear
C)
Equal to the instantaneous acceleration vector at the start of the motion done
clear
D)
A null vector done
clear
View Solution play_arrow
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question_answer46)
Radius of the curved road on national highway is \[R\]. Width of the road is \[b\]. The outer edge of the road is raised by \[h\] with respect to inner edge so that a car with velocity \[v\] can pass safe over it. The value of \[h\] is [MP PMT 1996]
A)
\[\frac{{{v}^{2}}b}{Rg}\] done
clear
B)
\[\frac{v}{Rgb}\] done
clear
C)
\[\frac{{{v}^{2}}R}{g}\] done
clear
D)
\[\frac{{{v}^{2}}b}{R}\] done
clear
View Solution play_arrow
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question_answer47)
When a particle moves in a uniform circular motion. It has
A)
Radial velocity and radial acceleration done
clear
B)
Tangential velocity and radial acceleration done
clear
C)
Tangential velocity and tangential acceleration done
clear
D)
Radial velocity and tangential acceleration done
clear
View Solution play_arrow
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question_answer48)
A motorcycle is going on an overbridge of radius \[R\]. The driver maintains a constant speed. As the motorcycle is ascending on the overbridge, the normal force on it [MP PET 1997]
A)
Increases done
clear
B)
Decreases done
clear
C)
Remains the same done
clear
D)
Fluctuates done
clear
View Solution play_arrow
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question_answer49)
A mass of 2 kg is whirled in a horizontal circle by means of a string at an initial speed of 5 revolutions per minute. Keeping the radius constant the tension in the string is doubled. The new speed is nearly [MP PMT/PET 1998; JIPMER 2000]
A)
14 rpm done
clear
B)
10 rpm done
clear
C)
2.25 rpm done
clear
D)
7 rpm done
clear
View Solution play_arrow
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question_answer50)
The magnitude of the centripetal force acting on a body of mass \[m\] executing uniform motion in a circle of radius \[r\] with speed \[v\] is [AFMC 1998; MP PET 1999]
A)
\[mvr\] done
clear
B)
\[\nu =\sqrt{\frac{rg(\tan \theta +\mu )}{1-\mu \tan \theta }}\] done
clear
C)
\[v/{{r}^{2}}m\] done
clear
D)
\[v/rm\] done
clear
View Solution play_arrow
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question_answer51)
A string breaks if its tension exceeds 10 newtons. A stone of mass 250 gm tied to this string of length 10 cm is rotated in a horizontal circle. The maximum angular velocity of rotation can be [MP PMT 1999]
A)
20 rad/s done
clear
B)
40 rad/s done
clear
C)
100 rad/s done
clear
D)
200 rad/s done
clear
View Solution play_arrow
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question_answer52)
A 500 kg car takes a round turn of radius 50 m with a velocity of 36 km/hr. The centripetal force is [KCET 2001; CBSE PMT 1999; JIPMER 2001, 02]
A)
250 N done
clear
B)
750 N done
clear
C)
1000 N done
clear
D)
1200 N done
clear
View Solution play_arrow
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question_answer53)
A ball of mass 0.25 kg attached to the end of a string of length 1.96 m is moving in a horizontal circle. The string will break if the tension is more than 25 N. What is the maximum speed with which the ball can be moved [CBSE PMT 1998]
A)
14 m/s done
clear
B)
3 m/s done
clear
C)
3.92 m/s done
clear
D)
5 m/s done
clear
View Solution play_arrow
-
question_answer54)
A body of mass 5 kg is moving in a circle of radius \[1\,m\] with an angular velocity of 2 radian/sec. The centripetal force is [AIIMS 1998]
A)
10 N done
clear
B)
20 N done
clear
C)
30 N done
clear
D)
40 N done
clear
View Solution play_arrow
-
question_answer55)
If a particle of mass \[m\] is moving in a horizontal circle of radius \[r\] with a centripetal force \[(-k/{{r}^{2}})\], the total energy is [EAMCET (Med.) 1995; AMU (Engg.) 2001]
A)
\[-\frac{k}{2r}\] done
clear
B)
\[-\frac{k}{r}\] done
clear
C)
\[-\frac{2k}{r}\] done
clear
D)
\[-\frac{4k}{r}\] done
clear
View Solution play_arrow
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question_answer56)
A stone of mass of 16 kg is attached to a string 144 m long and is whirled in a horizontal circle. The maximum tension the string can withstand is 16 Newton. The maximum velocity of revolution that can be given to the stone without breaking it, will be [SCRA 1994]
A)
20 \[m{{s}^{-1}}\] done
clear
B)
16 \[m{{s}^{-1}}\] done
clear
C)
14 \[m{{s}^{-1}}\] done
clear
D)
12 \[m{{s}^{-1}}\] done
clear
View Solution play_arrow
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question_answer57)
A circular road of radius 1000 m has banking angle \[{{45}^{o}}\]. The maximum safe speed of a car having mass 2000 kg will be, if the coefficient of friction between tyre and road is 0.5 [RPET 1997]
A)
172 m/s done
clear
B)
124 m/s done
clear
C)
99 m/s done
clear
D)
86 m/s done
clear
View Solution play_arrow
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question_answer58)
The second's hand of a watch has length 6 cm. Speed of end point and magnitude of difference of velocities at two perpendicular positions will be [RPET 1997]
A)
6.28 and 0 mm/s done
clear
B)
8.88 and 4.44 mm/s done
clear
C)
8.88 and 6.28 mm/s done
clear
D)
6.28 and 8.88 mm/s done
clear
View Solution play_arrow
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question_answer59)
A sphere of mass \[m\] is tied to end of a string of length \[l\] and rotated through the other end along a horizontal circular path with speed \[v\]. The work done in full horizontal circle is [CPMT 1993; JIPMER 2000]
A)
0 done
clear
B)
\[\left( \frac{m{{v}^{2}}}{l} \right)\,.\,2\pi l\] done
clear
C)
\[mg\,.\,2\pi l\] done
clear
D)
\[\left( \frac{m{{v}^{2}}}{l} \right)\,.\,(l)\] done
clear
View Solution play_arrow
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question_answer60)
A body is whirled in a horizontal circle of radius 20 cm. It has angular velocity of 10 rad/s. What is its linear velocity at any point on circular path [CBSE PMT 1996]
A)
10 m/s done
clear
B)
2 m/s done
clear
C)
20 m/s done
clear
D)
\[\sqrt{2}\] m/s done
clear
View Solution play_arrow
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question_answer61)
Find the maximum velocity for skidding for a car moved on a circular track of radius 100 m. The coefficient of friction between the road and tyre is 0.2 [CPMT 1996; Pb. PMT 2001]
A)
0.14 m/s done
clear
B)
140 m/s done
clear
C)
1.4 km/s done
clear
D)
14 m/s done
clear
View Solution play_arrow
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question_answer62)
A car when passes through a convex bridge exerts a force on it which is equal to [AFMC 1997]
A)
\[Mg+\frac{M{{v}^{2}}}{r}\] done
clear
B)
\[\frac{M{{v}^{2}}}{r}\] done
clear
C)
\[Mg\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer63)
The angular speed of seconds needle in a mechanical watch is [RPMT 1999; CPMT 1997; MH CET 2000, 01; BHU 2000]
A)
\[\frac{\pi }{30}\]rad/s done
clear
B)
\[2\pi \]rad/s done
clear
C)
\[\pi \]rad/s done
clear
D)
\[\frac{60}{\pi }\]rad/s done
clear
View Solution play_arrow
-
question_answer64)
The angular velocity of a particle rotating in a circular orbit 100 times per minute is [SCRA 1998; DPMT 2000]
A)
1.66 rad/s done
clear
B)
10.47 rad/s done
clear
C)
10.47 deg/s done
clear
D)
60 deg/s done
clear
View Solution play_arrow
-
question_answer65)
A body of mass 100 g is rotating in a circular path of radius r with constant velocity. The work done in one complete revolution is [AFMC 1998]
A)
100 rJ done
clear
B)
\[(r/100)J\] done
clear
C)
\[(100/r)J\] done
clear
D)
Zero done
clear
View Solution play_arrow
-
question_answer66)
A particle comes round a circle of radius 1 m once. The time taken by it is 10 sec. The average velocity of motion is [JIPMER 1999]
A)
0.2 \[\pi m/s\] done
clear
B)
\[2\,\,\pi m/s\] done
clear
C)
2 \[m/s\] done
clear
D)
Zero done
clear
View Solution play_arrow
-
question_answer67)
An unbanked curve has a radius of \[60\,m\]. The maximum speed at which a car can make a turn if the coefficient of static friction is 0.75, is [JIPMER 1999]
A)
2.1 \[m/s\] done
clear
B)
14 \[m/s\] done
clear
C)
21 \[m/s\] done
clear
D)
7 \[m/s\] done
clear
View Solution play_arrow
-
question_answer68)
A wheel completes 2000 revolutions to cover the 9.5 km. distance. then the diameter of the wheel is [RPMT 1999]
A)
1.5 m done
clear
B)
1.5 cm done
clear
C)
7.5 cm done
clear
D)
7.5 m done
clear
View Solution play_arrow
-
question_answer69)
A cycle wheel of radius 0.4 m completes one revolution in one second then the acceleration of a point on the cycle wheel will be [MH CET (Med.) 1999]
A)
0.8 m/s2 done
clear
B)
0.4 m/s2 done
clear
C)
\[1.6\,{{\pi }^{2}}\,m/{{s}^{2}}\] done
clear
D)
\[0.4\,{{\pi }^{2}}\,m/{{s}^{2}}\] done
clear
View Solution play_arrow
-
question_answer70)
The centripetal acceleration is given by [RPET 1999]
A)
v2/r done
clear
B)
vr done
clear
C)
vr2 done
clear
D)
v/r done
clear
View Solution play_arrow
-
question_answer71)
A cylindrical vessel partially filled with water is rotated about its vertical central axis. It?s surface will [RPET 2000]
A)
Rise equally done
clear
B)
Rise from the sides done
clear
C)
Rise from the middle done
clear
D)
Lowered equally done
clear
View Solution play_arrow
-
question_answer72)
If a particle covers half the circle of radius R with constant speed then [RPMT 2000]
A)
Momentum change is mvr done
clear
B)
Change in K.E. is 1/2 mv2 done
clear
C)
Change in K.E. is mv2 done
clear
D)
Change in K.E. is zero done
clear
View Solution play_arrow
-
question_answer73)
An aeroplane is flying with a uniform speed of 100 m/s along a circular path of radius 100 m. the angular speed of the aeroplane will be [KCET 2000]
A)
1 rad/sec done
clear
B)
2 rad/sec done
clear
C)
3 rad/sec done
clear
D)
4 rad/sec done
clear
View Solution play_arrow
-
question_answer74)
A body moves with constant angular velocity on a circle. Magnitude of angular acceleration [RPMT 2000]
A)
rw2 done
clear
B)
Constant done
clear
C)
Zero done
clear
D)
None of the above done
clear
View Solution play_arrow
-
question_answer75)
What is the value of linear velocity, if \[\vec{\omega }=3\hat{i}-4\hat{j}+\hat{k}\] and \[\vec{r}=5\hat{i}-6\hat{j}+6\hat{k}\] [Pb. PMT 2000]
A)
\[6\hat{i}+2\hat{j}-3\hat{k}\] done
clear
B)
\[-18\hat{i}-13\hat{j}+2\hat{k}\] done
clear
C)
\[4\hat{i}-13\hat{j}+6\hat{k}\] done
clear
D)
\[6\hat{i}-2\hat{j}+8\hat{k}\] done
clear
View Solution play_arrow
-
question_answer76)
A stone is tied to one end of a string 50 cm long is whirled in a horizontal circle with a constant speed. If the stone makes 10 revolutions in 20 s, what is the magnitude of acceleration of the stone [Pb. PMT 2000]
A)
493 cm/s2 done
clear
B)
720 cm/s2 done
clear
C)
860 cm/s2 done
clear
D)
990 cm/s2 done
clear
View Solution play_arrow
-
question_answer77)
A 100 kg car is moving with a maximum velocity of 9 m/s across a circular track of radius 30 m. The maximum force of friction between the road and the car is [Pb. PMT 2000]
A)
1000 N done
clear
B)
706 N done
clear
C)
270 N done
clear
D)
200 N done
clear
View Solution play_arrow
-
question_answer78)
The maximum speed of a car on a road?turn of radius 30 m, if the coefficient of friction between the tyres and the road is 0.4, will be [CBSE PMT 2000]
A)
10.84 m/sec done
clear
B)
9.84 m/sec done
clear
C)
8.84 m/sec done
clear
D)
6.84 m/sec done
clear
View Solution play_arrow
-
question_answer79)
The angular velocity of a wheel is 70 rad/sec. If the radius of the wheel is 0.5 m, then linear velocity of the wheel is [MH CET 2000]
A)
70 m/s done
clear
B)
35 m/s done
clear
C)
30 m/s done
clear
D)
20 m/s done
clear
View Solution play_arrow
-
question_answer80)
A cyclist goes round a circular path of circumference 34.3 m in \[\sqrt{22}\] sec. the angle made by him, with the vertical, will be [MH CET 2000]
A)
\[{{45}^{o}}\] done
clear
B)
\[{{40}^{o}}\] done
clear
C)
\[{{42}^{o}}\] done
clear
D)
\[{{48}^{o}}\] done
clear
View Solution play_arrow
-
question_answer81)
A particle of mass M is moving in a horizontal circle of radius R with uniform speed V. When it moves from one point to a diametrically opposite point, its [CBSE PMT 1992]
A)
Kinetic energy changes by \[M{{V}^{2}}/4\] done
clear
B)
Momentum does not change done
clear
C)
Momentum changes by 2MV done
clear
D)
Kinetic energy changes by \[M{{V}^{2}}\] done
clear
View Solution play_arrow
-
question_answer82)
A ball of mass 0.1 Kg. is whirled in a horizontal circle of radius 1 m. by means of a string at an initial speed of 10 R.P.M. Keeping the radius constant, the tension in the string is reduced to one quarter of its initial value. The new speed is [MP PMT 2001]
A)
5 r.p.m. done
clear
B)
10 r.p.m. done
clear
C)
20 r.p.m. done
clear
D)
14 r.p.m. done
clear
View Solution play_arrow
-
question_answer83)
A cyclist riding the bicycle at a speed of \[14\sqrt{3}\] ms?1 takes a turn around a circular road of radius \[20\sqrt{3}\] m without skidding. Given g = 9.8 ms?2, what is his inclination to the vertical [Kerala (Engg.) 2001]
A)
\[{{30}^{o}}\] done
clear
B)
\[{{90}^{o}}\] done
clear
C)
45 o done
clear
D)
\[{{60}^{o}}\] done
clear
View Solution play_arrow
-
question_answer84)
If a cycle wheel of radius 4 m completes one revolution in two seconds. Then acceleration of a point on the cycle wheel will be [Pb. PMT 2001]
A)
\[{{\pi }^{2}}m/{{s}^{2}}\] done
clear
B)
\[2{{\pi }^{2}}m/{{s}^{2}}\] done
clear
C)
\[4{{\pi }^{2}}m/{{s}^{2}}\] done
clear
D)
\[8\pi \,m/{{s}^{2}}\] done
clear
View Solution play_arrow
-
question_answer85)
A bob of mass 10 kg is attached to wire 0.3 m long. Its breaking stress is 4.8 × 107 N/m2. The area of cross section of the wire is 10?6 m2. The maximum angular velocity with which it can be rotated in a horizontal circle [Pb. PMT 2001]
A)
8 rad/sec done
clear
B)
4 rad/sec done
clear
C)
2 rad/sec done
clear
D)
1 rad/sec done
clear
View Solution play_arrow
-
question_answer86)
In uniform circular motion, the velocity vector and acceleration vector are [DCE 2000, 01, 03]
A)
Perpendicular to each other done
clear
B)
Same direction done
clear
C)
Opposite direction done
clear
D)
Not related to each other done
clear
View Solution play_arrow
-
question_answer87)
A point mass m is suspended from a light thread of length l, fixed at O, is whirled in a horizontal circle at constant speed as shown. From your point of view, stationary with respect to the mass, the forces on the mass are [AMU (Med.) 2001]
A)
B)
C)
D)
View Solution play_arrow
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question_answer88)
If a cyclist moving with a speed of 4.9 m/s on a level road can take a sharp circular turn of radius 4 m, then coefficient of friction between the cycle tyres and road is [AIIMS 1999; AFMC 2001]
A)
0.41 done
clear
B)
0.51 done
clear
C)
0.61 done
clear
D)
0.71 done
clear
View Solution play_arrow
-
question_answer89)
A car moves on a circular road. It describes equal angles about the centre in equal intervals of time. Which of the following statement about the velocity of the car is true [BHU 2001]
A)
Magnitude of velocity is not constant done
clear
B)
Both magnitude and direction of velocity change done
clear
C)
Velocity is directed towards the centre of the circle done
clear
D)
Magnitude of velocity is constant but direction changes done
clear
View Solution play_arrow
-
question_answer90)
A scooter is going round a circular road of radius 100 m at a speed of 10 m/s. The angular speed of the scooter will be [Pb. PMT 2002]
A)
0.01 rad/s done
clear
B)
0.1 rad/s done
clear
C)
1 rad/s done
clear
D)
10 rad/s done
clear
View Solution play_arrow
-
question_answer91)
A particle of mass M moves with constant speed along a circular path of radius r under the action of a force F. Its speed is [MP PMT 2002]
A)
\[\sqrt{\frac{r\,F}{m}}\] done
clear
B)
\[\sqrt{\frac{F}{r}}\] done
clear
C)
\[\sqrt{F\,m\,r}\] done
clear
D)
\[\sqrt{\frac{F}{m\,r}}\] done
clear
View Solution play_arrow
-
question_answer92)
In an atom for the electron to revolve around the nucleus, the necessary centripetal force is obtained from the following force exerted by the nucleus on the electron [MP PET 2002]
A)
Nuclear force done
clear
B)
Gravitational force done
clear
C)
Magnetic force done
clear
D)
Electrostatic force done
clear
View Solution play_arrow
-
question_answer93)
A particle moves with constant speed v along a circular path of radius r and completes the circle in time T. The acceleration of the particle is [Orissa JEE 2002]
A)
\[2\,\pi \,v/T\] done
clear
B)
\[2\,\pi \,r/T\] done
clear
C)
\[2\,\pi \,{{r}^{2}}/T\] done
clear
D)
\[2\,\pi \,{{v}^{2}}/T\] done
clear
View Solution play_arrow
-
question_answer94)
The maximum velocity \[\left( inm{{s}^{1}} \right)\] with which a car driver must traverse a flat curve of radius 150 m and coefficient of friction 0.6 to avoid skidding is [AIEEE 2002]
A)
60 done
clear
B)
30 done
clear
C)
15 done
clear
D)
25 done
clear
View Solution play_arrow
-
question_answer95)
A car is moving with high velocity when it has a turn. A force acts on it outwardly because of [AFMC 2002]
A)
Centripetal force done
clear
B)
Centrifugal force done
clear
C)
Gravitational force done
clear
D)
All the above done
clear
View Solution play_arrow
-
question_answer96)
A motor cycle driver doubles its velocity when he is having a turn. The force exerted outwardly will be [AFMC 2002]
A)
Double done
clear
B)
Half done
clear
C)
4 times done
clear
D)
\[\frac{1}{4}\] times done
clear
View Solution play_arrow
-
question_answer97)
The coefficient of friction between the tyres and the road is 0.25. The maximum speed with which a car can be driven round a curve of radius 40 m without skidding is (assume \[g=10m{{s}^{2}}\]) [Kerala (Med.) 2002]
A)
\[40m{{s}^{1}}\] done
clear
B)
\[20m{{s}^{1}}\] done
clear
C)
\[15m{{s}^{1}}\] done
clear
D)
\[10m{{s}^{1}}\] done
clear
View Solution play_arrow
-
question_answer98)
An athlete completes one round of a circular track of radius 10 m in 40 sec. The distance covered by him in 2 min 20 sec is [Kerala (Med.) 2002]
A)
70 m done
clear
B)
140 m done
clear
C)
110 m done
clear
D)
220 m done
clear
View Solution play_arrow
-
question_answer99)
A proton of mass 1.6 × 10?27 kg goes round in a circular orbit of radius 0.10 m under a centripetal force of 4 × 10?13 N. then the frequency of revolution of the proton is about [Kerala (Med.) 2002]
A)
0.08 × 108 cycles per sec done
clear
B)
4 × 108 cycles per sec done
clear
C)
8 × 108 cycles per sec done
clear
D)
12 × 108 cycles per sec done
clear
View Solution play_arrow
-
question_answer100)
A particle is moving in a circle with uniform speed v. In moving from a point to another diametrically opposite point [Orissa JEE 2003]
A)
The momentum changes by mv done
clear
B)
The momentum changes by 2mv done
clear
C)
The kinetic energy changes by (1/2)mv2 done
clear
D)
The kinetic energy changes by mv2 done
clear
View Solution play_arrow
-
question_answer101)
In uniform circular motion [MP PMT 1994]
A)
Both the angular velocity and the angular momentum vary done
clear
B)
The angular velocity varies but the angular momentum remains constant done
clear
C)
Both the angular velocity and the angular momentum stay constant done
clear
D)
The angular momentum varies but the angular velocity remains constant done
clear
View Solution play_arrow
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question_answer102)
When a body moves in a circular path, no work is done by the force since, [KCET 2004]
A)
There is no displacement done
clear
B)
There is no net force done
clear
C)
Force and displacement are perpendicular to each other done
clear
D)
The force is always away from the centre done
clear
View Solution play_arrow
-
question_answer103)
Which of the following statements is false for a particle moving in a circle with a constant angular speed [AIEEE 2004]
A)
The velocity vector is tangent to the circle done
clear
B)
The acceleration vector is tangent to the circle done
clear
C)
The acceleration vector points to the centre of the circle done
clear
D)
The velocity and acceleration vectors are perpendicular to each other done
clear
View Solution play_arrow
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question_answer104)
If \[{{a}_{r}}\] and \[{{a}_{t}}\]represent radial and tangential accelerations, the motion of a particle will be uniformly circular if [CPMT 2004]
A)
\[{{a}_{r}}=0\] and \[{{a}_{t}}=0\] done
clear
B)
\[{{a}_{r}}=0\] but \[{{a}_{t}}\ne 0\] done
clear
C)
\[{{a}_{r}}\ne 0\] but \[{{a}_{t}}=0\] done
clear
D)
\[{{a}_{r}}\ne 0\] and \[{{a}_{t}}\ne 0\] done
clear
View Solution play_arrow
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question_answer105)
A person with his hands in his pockets is skating on ice at the velocity of 10 m/s and describes a circle of radius 50 m. What is his inclination with vertical [Pb. PET 2000]
A)
\[\frac{\sqrt{3}}{2}.\] done
clear
B)
\[{{\tan }^{-1}}\left( \frac{3}{5} \right)\] done
clear
C)
\[{{\tan }^{-1}}(1)\] done
clear
D)
\[{{\tan }^{-1}}\left( \frac{1}{5} \right)\] done
clear
View Solution play_arrow
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question_answer106)
If the radius of curvature of the path of two particles of same masses are in the ratio 1 : 2, then in order to have constant centripetal force, their velocity, should be in the ratio of [Pb. PET 2000]
A)
1 : 4 done
clear
B)
4 : 1 done
clear
C)
\[\sqrt{2}\,\,:\,\,1\] done
clear
D)
\[1\,\,:\,\,\sqrt{2}\] done
clear
View Solution play_arrow
-
question_answer107)
An object is moving in a circle of radius 100 m with a constant speed of 31.4 m/s. What is its average speed for one complete revolution [DCE 2004]
A)
Zero done
clear
B)
31.4 m/s done
clear
C)
3.14 m/s done
clear
D)
\[\sqrt{2}\times 31.4\,\,m/s\] done
clear
View Solution play_arrow
-
question_answer108)
A body of mass 1 kg tied to one end of string is revolved in a horizontal circle of radius 0.1 m with a speed of 3 revolution/sec, assuming the effect of gravity is negligible, then linear velocity, acceleration and tension in the string will be [DPMT 2003]
A)
\[1.88\,\,m/s,\,\,35.5\,\,m/{{s}^{2}},\,\,35.5\,\,N\] done
clear
B)
\[2.88\,\,m/s,\,\,45.5\,\,m/{{s}^{2}},\,\,45.5\,\,N\] done
clear
C)
\[3.88\,\,m/s,\,\,55.5\,\,m/{{s}^{2}},\,\,55.5\,\,N\] done
clear
D)
None of these done
clear
View Solution play_arrow
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question_answer109)
The acceleration of a train travelling with speed of 400 m/s as it goes round a curve of radius 160 m, is [Pb. PET 2003]
A)
\[1\,\,km/{{s}^{2}}\] done
clear
B)
\[100\,\,\,m/{{s}^{2}}\] done
clear
C)
\[10\,\,m/{{s}^{2}}\] done
clear
D)
\[1\,\,m/{{s}^{2}}\] done
clear
View Solution play_arrow
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question_answer110)
A car of mass 800 kg moves on a circular track of radius 40 m. If the coefficient of friction is 0.5, then maximum velocity with which the car can move is [MH CET 2004]
A)
7 m/s done
clear
B)
14 m/s done
clear
C)
8 m/s done
clear
D)
12 m/s done
clear
View Solution play_arrow
-
question_answer111)
A 500 kg crane takes a turn of radius 50 m with velocity of 36 km/hr. The centripetal force is [Pb. PMT 2003]
A)
1200 N done
clear
B)
1000 N done
clear
C)
750 N done
clear
D)
250 N done
clear
View Solution play_arrow
-
question_answer112)
Two bodies of equal masses revolve in circular orbits of radii \[{{R}_{1}}\] and \[{{R}_{2}}\] with the same period. Their centripetal forces are in the ratio [Kerala PMT 2004]
A)
\[{{\left( \frac{{{R}_{2}}}{{{R}_{1}}} \right)}^{2}}\] done
clear
B)
\[\frac{{{R}_{1}}}{{{R}_{2}}}\] done
clear
C)
\[{{\left( \frac{{{R}_{1}}}{{{R}_{2}}} \right)}^{2}}\] done
clear
D)
\[\sqrt{{{R}_{1}}{{R}_{2}}}\] done
clear
View Solution play_arrow
-
question_answer113)
In case of uniform circular motion which of the following physical quantity do not remain constant [Kerala PMT 2004]
A)
Speed done
clear
B)
Momentum done
clear
C)
Kinetic energy done
clear
D)
Mass done
clear
View Solution play_arrow
-
question_answer114)
What happens to the centripetal acceleration of a revolving body if you double the orbital speed \[v\] and half the angular velocity \[\omega \]
A)
The centripetal acceleration remains unchanged done
clear
B)
The centripetal acceleration is halved done
clear
C)
The centripetal acceleration is doubled done
clear
D)
The centripetal acceleration is quadrupled done
clear
View Solution play_arrow
-
question_answer115)
A mass is supported on a frictionless horizontal surface. It is attached to a string and rotates about a fixed centre at an angular velocity \[{{\omega }_{0}}\]. If the length of the string and angular velocity are doubled, the tension in the string which was initially \[{{T}_{0}}\] is now [AIIMS 1985]
A)
\[{{T}_{0}}\] done
clear
B)
\[{{T}_{0}}/2\] done
clear
C)
\[4{{T}_{0}}\] done
clear
D)
\[8{{T}_{0}}\] done
clear
View Solution play_arrow
-
question_answer116)
In 1.0 s, a particle goes from point A to point B, moving in a semicircle of radius 1.0 m (see figure). The magnitude of the average velocity is [IIT-JEE 1999]
A)
\[3.14m/s\] done
clear
B)
2.0 \[m/s\] done
clear
C)
1.0 \[m/s\] done
clear
D)
Zero done
clear
View Solution play_arrow
-
question_answer117)
Three identical particles are joined together by a thread as shown in figure. All the three particles are moving in a horizontal plane. If the velocity of the outermost particle is v0, then the ratio of tensions in the three sections of the string is [UPSEAT 2003]
A)
3 : 5 : 7 done
clear
B)
3 : 4 : 5 done
clear
C)
7 : 11 : 6 done
clear
D)
3 : 5 : 6 done
clear
View Solution play_arrow
-
question_answer118)
A particle is moving in a circle of radius R with constant speed v, if radius is double then its centripetal force to keep the same speed should be [BCECE 2005]
A)
Doubled done
clear
B)
Halved done
clear
C)
Quadrupled done
clear
D)
Unchanged done
clear
View Solution play_arrow
-
question_answer119)
A stone ties to the end of a string \[1m\] long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolution in 44 seconds, what is the magnitude and direction of acceleration of the stone [CBSE PMT 2005]
A)
\[\frac{{{\pi }^{2}}}{4}m{{s}^{-2}}\] and direction along the radius towards the centre done
clear
B)
\[{{\pi }^{2}}m{{s}^{-2}}\] and direction along the radius away from the centre done
clear
C)
\[{{\pi }^{2}}m{{s}^{-2}}\] and direction along the radius towards the centre done
clear
D)
\[{{\pi }^{2}}m{{s}^{-2}}\] and direction along the tangent to the circle done
clear
View Solution play_arrow
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question_answer120)
A particle describes a horizontal circle in a conical funnel whose inner surface is smooth with speed of 0.5 m/s. What is the height of the plane of circle from vertex of the funnel ? [J&K CET 2005]
A)
0.25 cm done
clear
B)
2 cm done
clear
C)
4 cm done
clear
D)
2.5 cm done
clear
View Solution play_arrow
-
question_answer121)
What is the angular velocity of earth [Orissa JEE 2005]
A)
\[\frac{2\pi }{86400}rad/\sec \] done
clear
B)
\[\frac{2\pi }{3600}rad/\sec \] done
clear
C)
\[\frac{2\pi }{24}rad/\sec \] done
clear
D)
\[\frac{2\pi }{6400}rad/\sec \] done
clear
View Solution play_arrow
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question_answer122)
If the length of the second's hand in a stop clock is 3 cm the angular velocity and linear velocity of the tip is [Kerala PET 2005]
A)
0.2047 rad/sec., 0.0314 m/sec done
clear
B)
0.2547 rad/sec., 0.314 m/sec done
clear
C)
0.1472 rad/sec., 0.06314 m/sec done
clear
D)
0.1047 rad/sec., 0.00314 m/sec done
clear
View Solution play_arrow