
question_answer1) A particle moves in a straight line in such a way that its velocity at any point is given by \[{{v}^{2}}=23x\], where x is measured from a fixed point. The acceleration is [MP PET 1992]
A) Uniform done
clear
B) Zero done
clear
C) Nonuniform done
clear
D) Indeterminate done
clear
View Solution play_arrow

question_answer2) A stone is falling freely and describes a distance s in t seconds given by equation \[s=\frac{1}{2}g\,{{t}^{2}}\]. The acceleration of the stone is
A) Uniform done
clear
B) Zero done
clear
C) Nonuniform done
clear
D) Indeterminate done
clear
View Solution play_arrow

question_answer3) The radius of a sphere is measured to be 20 cm with a possible error of 0.02 of a cm. The consequent error in the surface of the sphere is
A) \[10.5\] sq cm done
clear
B) 5.025 sq cm done
clear
C) 10.05 sq cm done
clear
D) None of these done
clear
View Solution play_arrow

question_answer4) The displacement of a particle in time t is given by \[s=2{{t}^{2}}3t+1\]. The acceleration is
A) 1 done
clear
B) 3 done
clear
C) 4 done
clear
D) 5 done
clear
View Solution play_arrow

question_answer5) The equation of motion of a particle is given by \[s=2{{t}^{3}}9{{t}^{2}}+12t+1\],where s and t are measured in cm and sec. The time when the particle stops momentarily is
A) 1 sec done
clear
B) 2 sec done
clear
C) 1, 2 sec done
clear
D) None of these done
clear
View Solution play_arrow

question_answer6) If a spherical balloon has a variable diameter \[3x+\frac{9}{2}\], then the rate of change of its volume with respect to x is
A) \[27\pi {{(2x+3)}^{2}}\] done
clear
B) \[\frac{27\pi }{16}{{(2x+3)}^{2}}\] done
clear
C) \[\frac{27\pi }{8}{{(2x+3)}^{2}}\] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer7) The velocity of a particle at time t is given by the relation \[v=6t\frac{{{t}^{2}}}{6}\]. The distance traveled in 3 seconds is, if \[s=0\]at \[t=0\]
A) \[\frac{39}{2}\] done
clear
B) \[\frac{57}{2}\] done
clear
C) \[\frac{51}{2}\] done
clear
D) \[\frac{33}{2}\] done
clear
View Solution play_arrow

question_answer8) The equation of motion of a car is \[s={{t}^{2}}2t\], where t is measured in hours and s in kilometers. When the distance travelled by the car is \[15\,km\], the velocity of the car is
A) \[2\,km/h\] done
clear
B) \[4\,km/h\] done
clear
C) \[2\,km/h\] done
clear
D) \[8\,km/h\] done
clear
View Solution play_arrow

question_answer9) A stone moving vertically upwards has its equation of motion \[s=490t4.9{{t}^{2}}\]. The maximum height reached by the stone is
A) 12250 done
clear
B) 1225 done
clear
C) 36750 done
clear
D) None of these done
clear
View Solution play_arrow

question_answer10) The edge of a cube is increasing at the rate of \[5cm/\sec .\]How fast is the volume of the cube increasing when the edge is 12cm long
A) \[432\,c{{m}^{3}}/\sec \] done
clear
B) \[2160\,c{{m}^{3}}/\sec \] done
clear
C) \[180\,c{{m}^{3}}/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer11) If the law of motion in a straight line is \[s=\frac{1}{2}v\,t,\] then acceleration is [MP PET 1991]
A) Constant done
clear
B) Proportional to t done
clear
C) Proportional to v done
clear
D) Proportional to s done
clear
View Solution play_arrow

question_answer12) A point moves in a straight line during the time \[t=0\] to \[t=3\]according to the law \[s=15t2{{t}^{2}}\]. The average velocity is [MP PET 1992]
A) 3 done
clear
B) 9 done
clear
C) 15 done
clear
D) 27 done
clear
View Solution play_arrow

question_answer13) The distance in seconds, described by a particle in t seconds is given by \[s=a{{e}^{t}}+\frac{b}{{{e}^{t}}}\]. Then acceleration of the particle at time t is
A) Proportional to t done
clear
B) Proportional to s done
clear
C) s done
clear
D) Constant done
clear
View Solution play_arrow

question_answer14) The equation of motion of a stone, thrown vertically upwards is \[s=ut6.3{{t}^{2}},\]where the units of s and t are cm and sec. If the stone reaches at maximum height in 3 sec, then u =
A) \[18.9\,\,cm/\sec \] done
clear
B) \[12.6\,\,cm/\sec \] done
clear
C) \[37.8\,\,cm/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer15) A particle moves in a straight line so that its velocity at any point is given by \[{{v}^{2}}=a+bx\], where \[a,b\ne 0\]are constants. The acceleration is [MP PET 1989]
A) Zero done
clear
B) Uniform done
clear
C) Nonuniform done
clear
D) Indeterminate done
clear
View Solution play_arrow

question_answer16) The volume V and depth x of water in a vessel are connected by the relation \[V=5x\frac{{{x}^{2}}}{6}\]and the volume of water is increasing at the rate of \[5c{{m}^{3}}/\sec \], when \[x=2cm\]. The rate at which the depth of water is increasing, is
A) \[\frac{5}{18}cm/\sec \] done
clear
B) \[\frac{1}{4}cm/\sec \] done
clear
C) \[\frac{5}{16}cm/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer17) The equation of motion of a stone thrown vertically upward from the surface of a planet is given by \[s=10\,\,t3{{t}^{2}}\], and the units of s and t are cm and sec respectively. The stone will return to the surface of the planet after
A) \[\frac{10}{3}\sec \] done
clear
B) \[\frac{5}{3}\sec \] done
clear
C) \[\frac{20}{3}\sec \] done
clear
D) \[\frac{5}{6}\sec \] done
clear
View Solution play_arrow

question_answer18) A body moves according to the formula \[v=1+{{t}^{2}}\], where v is the velocity at time t. The acceleration after 3 sec will be (v in cm/sec) [MP PET 1988]
A) \[24\,cm/{{\sec }^{2}}\] done
clear
B) \[12\,cm/{{\sec }^{2}}\] done
clear
C) \[6\,cm/{{\sec }^{2}}\] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer19) The length of the side of a square sheet of metal is increasing at the rate of \[4cm/\sec \]. The rate at which the area of the sheet is increasing when the length of its side is 2 cm, is
A) \[16\,c{{m}^{2}}/\sec \] done
clear
B) \[8\,c{{m}^{2}}/\sec \] done
clear
C) \[32\,c{{m}^{2}}/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer20) The equations of motion of two stones thrown vertically upwards simultaneously are \[s=19.6\,t4.9\,{{t}^{2}}\] and \[s=9.8\,t4.9\,{{t}^{2}}\] respectively and the maximum height attained by the first one is h. When the height of the first stone is maximum, the height of the second stone will be
A) h/3 done
clear
B) 2h done
clear
C) h done
clear
D) 0 done
clear
View Solution play_arrow

question_answer21) The maximum height is reached in 5 seconds by a stone thrown vertically upwards and moving under the equation 10s = 10ut ? 49\[{{t}^{2}}\], where s is in metre and t is in second. The value of u is
A) \[4.9m/\sec \] done
clear
B) \[49m/\sec \] done
clear
C) \[98m/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer22) If \[2t={{v}^{2}},\]then \[\frac{dv}{dt}\]is equal to [MP PET 1992]
A) 0 done
clear
B) 1/4 done
clear
C) 1/2 done
clear
D) 1/v done
clear
View Solution play_arrow

question_answer23) If \[t=\frac{{{v}^{2}}}{2}\],then \[\left( \frac{df}{dt} \right)\]is equal to, (where f is acceleration) [MP PET 1991]
A) \[{{f}^{2}}\] done
clear
B) \[{{f}^{3}}\] done
clear
C) \[{{f}^{3}}\] done
clear
D) \[{{f}^{2}}\] done
clear
View Solution play_arrow

question_answer24) The equation of motion of a particle moving along a straight line is \[s=2\]\[{{t}^{3}}9{{t}^{2}}+12t\], where the units of s and t are cm and sec. The acceleration of the particle will be zero after
A) \[\frac{3}{2}\,sec\] done
clear
B) \[\frac{2}{3}sec\] done
clear
C) \[\frac{1}{2}sec\] done
clear
D) Never done
clear
View Solution play_arrow

question_answer25) A particle is moving in a straight line according to the formula \[s={{t}^{2}}+8t+12.\]If s be measured in metre and t be measured in second, then the average velocity of the particle in third second is
A) \[14\,m/\sec \] done
clear
B) \[13\,m/\sec \] done
clear
C) \[15\,m/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer26) A 10cm long rod AB moves with its ends on two mutually perpendicular straight lines OX and OY. If the end A be moving at the rate of \[2cm/\sec \], then when the distance of A from O is \[8cm\], the rate at which the end B is moving, is [SCRA 1996]
A) \[\frac{8}{3}cm/\sec \] done
clear
B) \[\frac{4}{3}cm/\sec \] done
clear
C) \[\frac{2}{9}cm/\sec \] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer27) If the radius of a circle increases from 3 cm to 3.2 cm, then the increase in the area of the circle is
A) \[1.2\pi \,\,c{{m}^{2}}\] done
clear
B) \[12\pi \,\,c{{m}^{2}}\] done
clear
C) \[6\pi \,\,c{{m}^{2}}\] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer28) If \[y={{x}^{3}}+5\]and x changes from 3 to 2.99, then the approximate change in y is
A) 2.7 done
clear
B) ? 0. 27 done
clear
C) 27 done
clear
D) None of these done
clear
View Solution play_arrow

question_answer29) A particle is moving on a straight line, where its position s (in metre) is a function of time t (in seconds) given by \[s=a{{t}^{2}}+bt+6,t\ge 0\]. If it is known that the particle comes to rest after 4 seconds at a distance of 16 metre from the starting position \[(t=0)\], then the retardation in its motion is [MP PET 1993]
A) \[1m/{{\sec }^{2}}\] done
clear
B) \[\frac{5}{4}m/{{\sec }^{2}}\] done
clear
C) \[\frac{1}{2}m/{{\sec }^{2}}\] done
clear
D) \[\frac{5}{4}m/{{\sec }^{2}}\] done
clear
View Solution play_arrow

question_answer30) A particle is moving in a straight line according as \[s=45\,t+11{{t}^{2}}{{t}^{3}}\]then the time when it will come to rest, is
A) ? 9 seconds done
clear
B) \[\frac{5}{3}\]seconds done
clear
C) 9 seconds done
clear
D) \[\frac{5}{3}\]seconds done
clear
View Solution play_arrow

question_answer31) A ball thrown vertically upwards falls back on the ground after 6 second. Assuming that the equation of motion is of the form \[s=ut4.9{{t}^{2}}\], where s is in metre and t is in second, find the velocity at \[t=0\]
A) \[0\,m/s\] done
clear
B) 1 m/s done
clear
C) 29.4 m/s done
clear
D) None of these done
clear
View Solution play_arrow

question_answer32) Radius of a circle is increasing uniformly at the rate of \[3cm/\sec .\]The rate of increasing of area when radius is \[10cm\], will be
A) \[\pi \,c{{m}^{2}}/s\] done
clear
B) \[2\pi \,c{{m}^{2}}/s\] done
clear
C) \[10\pi \,c{{m}^{2}}/s\] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer33) The motion of stone thrown up vertically is given by \[s=13.8t4.9{{t}^{2}}\], where s is in metre and t is in seconds. Then its velocity at \[t=1\] second is
A) 3 m/s done
clear
B) 5 m/s done
clear
C) 4 m/s done
clear
D) None of these done
clear
View Solution play_arrow

question_answer34) A particle is moving in a straight line. Its displacement at time t is given by \[s=4{{t}^{2}}+2t\], then its velocity and acceleration at time \[t=\frac{1}{2}\] second are [AISSE 1981]
A) ? 2, ? 8 done
clear
B) 2, 6 done
clear
C) ? 2, 8 done
clear
D) 2, 8 done
clear
View Solution play_arrow

question_answer35) If the distance travelled by a point in time t is \[s=180t16{{t}^{2}}\], then the rate of change in velocity is [MP PET 1995]
A) ? 16 t unit done
clear
B) 48 unit done
clear
C) ? 32 unit done
clear
D) None of these done
clear
View Solution play_arrow

question_answer36) A man 2metre high walks at a uniform speed 5 metre/hour away from a lamp post 6 metre high. The rate at which the length of his shadow increases is
A) 5 m/h done
clear
B) \[\frac{5}{2}\]m/h done
clear
C) \[\frac{5}{3}\]m/h done
clear
D) \[\frac{5}{4}\]m/h done
clear
View Solution play_arrow

question_answer37) A ladder 5 m in length is resting against vertical wall. The bottom of the ladder is pulled along the ground away from the wall at the rate of \[1.5\,m/\sec \]. The length of the highest point of the ladder when the foot of the ladder \[4.0\,m\] away from the wall decreases at the rate of [Kurukshetra CEE 1996]
A) 2 m/sec done
clear
B) 3 m/sec done
clear
C) 2.5 m/sec done
clear
D) 1.5 m/sec done
clear
View Solution play_arrow

question_answer38) If by dropping a stone in a quiet lake a wave moves in circle at a speed of 3.5 cm/sec, then the rate of increase of the enclosed circular region when the radius of the circular wave is 10 cm, is \[\left( \pi =\frac{22}{7} \right)\] [MP PET 1998]
A) 220 sq. cm/sec done
clear
B) 110 sq. cm/sec done
clear
C) 35 sq. cm/sec done
clear
D) 350 sq. cm/sec done
clear
View Solution play_arrow

question_answer39) A ladder is resting with the wall at an angle of \[{{30}^{o}}\]. A man is ascending the ladder at the rate of 3 ft/sec. His rate of approaching the wall is
A) 3 ft/sec done
clear
B) \[\frac{3}{2}\]ft/sec done
clear
C) \[\frac{3}{4}\]ft/sec done
clear
D) \[\frac{3}{\sqrt{2}}\]ft/sec done
clear
View Solution play_arrow

question_answer40) If the edge of a cube increases at the rate of 60 cm per second, at what rate the volume is increasing when the edge is 90 cm
A) 486000 cu cm per sec done
clear
B) 1458000 cu cm per sec done
clear
C) 43740000 cu cm per sec done
clear
D) None of these done
clear
View Solution play_arrow

question_answer41) If the distance ?s? traveled by a particle in time t is\[s=a\sin t+b\cos 2t\], then the acceleration at t = 0 is
A) a done
clear
B) ? a done
clear
C) 4b done
clear
D) ? 4b done
clear
View Solution play_arrow

question_answer42) A particle moves so that \[S=6+48t{{t}^{3}}\]. The direction of motion reverses after moving a distance of [Kurukshetra CEE 1998]
A) 63 done
clear
B) 104 done
clear
C) 134 done
clear
D) 288 done
clear
View Solution play_arrow

question_answer43) If the volume of a spherical balloon is increasing at the rate of 900cm3per sec, then the rate of change of radius of balloon at instant when radius is 15cm [in cm/sec] [RPET 1996]
A) \[\frac{22}{7}\] done
clear
B) 22 done
clear
C) \[\frac{7}{22}\] done
clear
D) None of these done
clear
View Solution play_arrow

question_answer44) If the path of a moving point is the curve \[x=at\], \[y=b\sin at\], then its acceleration at any instant [SCRA 1996]
A) Is constant done
clear
B) Varies as the distance from the axis of x done
clear
C) Varies as the distance from the axis of y done
clear
D) Varies as the distance of the point from the origin done
clear
View Solution play_arrow

question_answer45) If the rate of increase of area of a circle is not constant but the rate of increase of perimeter is constant, then the rate of increase of area varies [SCRA 1996]
A) As the square of the perimeter done
clear
B) Inversely as the perimeter done
clear
C) As the radius done
clear
D) Inversely as the radius done
clear
View Solution play_arrow

question_answer46) A stone thrown vertically upwards rises ?s? metre in t seconds, where \[s=80t16{{t}^{2}}\], then the velocity after 2 seconds is [SCRA 1996]
A) 8 m per sec done
clear
B) 16 m per sec done
clear
C) 32 m per sec done
clear
D) 64 m per sec done
clear
View Solution play_arrow

question_answer47) A particle moves along a straight line so that its distance s in time t sec is \[s=t+6{{t}^{2}}{{t}^{3}}\]. After what time is the acceleration zero [AMU 1999]
A) 2 sec done
clear
B) 3 sec done
clear
C) 4 sec done
clear
D) 6 sec done
clear
View Solution play_arrow

question_answer48) The distance s metre covered by a body in t seconds is given by \[s=3{{t}^{2}}8t+5,\]the body will stop after [RPET 2000]
A) 1 sec done
clear
B) 3/4 sec done
clear
C) 4/3 sec done
clear
D) 4 sec done
clear
View Solution play_arrow

question_answer49) The rate of change of \[\sqrt{({{x}^{2}}+16)}\] with respect to \[\frac{x}{x1}\] at \[x=3\] is [AMU 2001; MP PET 1987]
A) 2 done
clear
B) \[\frac{11}{5}\] done
clear
C) \[\frac{12}{5}\] done
clear
D) \[3\] done
clear
View Solution play_arrow

question_answer50) The speed \[v\] of a particle moving along a straight line is given by \[a+b{{v}^{2}}={{x}^{2}}\] (where x is its distance from the origin). The acceleration of the particle is [MP PET 2002]
A) \[bx\] done
clear
B) \[x/a\] done
clear
C) \[x/b\] done
clear
D) \[x/ab\] done
clear
View Solution play_arrow

question_answer51) A particle is moving along the curve \[x=a{{t}^{2}}+bt+c.\]If \[ac={{b}^{2}},\] then the particle would be moving with uniform [Orissa JEE 2003]
A) Rotation done
clear
B) Velocity done
clear
C) Acceleration done
clear
D) Retardation done
clear
View Solution play_arrow

question_answer52) The sides of an equilateral triangle are increasing at the rate of 2 cm/sec. The rate at which the area increases, when the side is 10 cm is [Kerala (Engg.) 2002]
A) \[\sqrt{3}\] sq. unit/sec done
clear
B) 10 sq. unit/sec done
clear
C) \[10\sqrt{3}\] sq. unit/sec done
clear
D) \[\frac{10}{\sqrt{3}}\] sq. unit/sec done
clear
View Solution play_arrow

question_answer53) The rate of change of the surface area of a sphere of radius r when the radius is increasing at the rate of 2 cm/sec is proportional to [Karnataka CET 2003]
A) \[\frac{1}{r}\] done
clear
B) \[\frac{1}{{{r}^{2}}}\] done
clear
C) \[\because \]Surface area \[s=4\pi {{r}^{2}}\] and \[\frac{dr}{dt}=2\] \ \[\frac{ds}{dt}=4\pi \times 2r\frac{dr}{dt}\] = \[8\pi r\times 2=16\pi r\]? \[\frac{ds}{dt}\propto r\]. done
clear
D) \[{{r}^{2}}\] done
clear
View Solution play_arrow

question_answer54) Moving along the xaxis are two points with \[x=10+6t;x=3+{{t}^{2}}.\]The speed with which they are reaching from each other at the time of encounter is (x is in cm and t is in seconds) [MP PET 2003]
A) 16 cm/sec done
clear
B) 20 cm/sec done
clear
C) 8 cm/sec done
clear
D) 12 cm/sec done
clear
View Solution play_arrow

question_answer55) The position of a point in time ?t? is given by \[x=a+btc{{t}^{2}}\], \[y=at+b{{t}^{2}}\]. Its acceleration at time ?t? is [MP PET 2003]
A) \[bc\] done
clear
B) \[b+c\] done
clear
C) \[2b2c\] done
clear
D) \[2\sqrt{{{b}^{2}}+{{c}^{2}}}\] done
clear
View Solution play_arrow

question_answer56) Gas is being pumped into a spherical balloon at the rate of 30 ft3/min. Then the rate at which the radius increases when it reaches the value 15 ft is [EAMCET 2003]
A) \[\frac{1}{30\pi }ft/\min \text{.}\] done
clear
B) \[\frac{1}{15\pi }ft/\min \text{.}\] done
clear
C) \[\frac{1}{20}ft/\min \text{.}\] done
clear
D) \[\frac{1}{25}ft/\min \text{.}\] done
clear
View Solution play_arrow

question_answer57) If the distance ?s? metre traversed by a particle in t seconds is given by \[s={{t}^{3}}3{{t}^{2}}\], then the velocity of the particle when the acceleration is zero, in metre/sec is [Karnataka CET 2004]
A) 3 done
clear
B) ? 2 done
clear
C) ? 3 done
clear
D) 2 done
clear
View Solution play_arrow

question_answer58) A particle moves in a straight line so that \[s=\sqrt{t}\], then its acceleration is proportional to [MP PET 2004]
A) Velocity done
clear
B) (Velocity)3/2 done
clear
C) (Velocity) 3 done
clear
D) (Velocity)2 done
clear
View Solution play_arrow

question_answer59) A point on the parabola \[{{y}^{2}}=18x\]at which the ordinate increases at twice the rate of the abscissa is [AIEEE 2004]
A) \[\left( \frac{9}{8},\frac{9}{2} \right)\] done
clear
B) (2, ? 4) done
clear
C) \[\left( \frac{9}{8},\frac{9}{2} \right)\] done
clear
D) (2, 4) done
clear
View Solution play_arrow

question_answer60) A spherical iron ball 10 cm in radius is coated with a layer of ice of uniform thickness that melts at a rate of 50 cm3/min. When the thickness of ice is 5 cm, then the rate at which the thickness of ice decreases, is [AIEEE 2005]
A) \[\frac{1}{54\pi }\]cm/min done
clear
B) \[\frac{5}{6\pi }\] cm/min done
clear
C) \[\frac{1}{36\pi }\] cm/min done
clear
D) \[\frac{1}{18\pi }\] cm/min done
clear
View Solution play_arrow

question_answer61) A spherical balloon is being inflated at the rate of 35 cc/min. The rate of increase of the surface area of the balloon when its diameter is 14 cm is [Karnataka CET 2005]
A) 7 sq. cm/min done
clear
B) 10 sq. cm/min done
clear
C) 17.5 sq. cm/min done
clear
D) 28 sq. cm/min done
clear
View Solution play_arrow

question_answer62) A population p(t) of 1000 bacteria introduced into nutrient medium grows according to the relation \[p(t)=1000+\frac{1000t}{100+{{t}^{2}}}\]. The maximum size of this bacterial population is [Karnataka CET 2005]
A) 1100 done
clear
B) 1250 done
clear
C) 1050 done
clear
D) 5250 done
clear
View Solution play_arrow

question_answer63) If a particle moves such that the displacement is proportional to the square of the velocity acquired, then its acceleration is [Kerala (Engg.) 2005]
A) Proportion to\[{{s}^{2}}\] done
clear
B) Proportional to \[1/{{s}^{2}}\] done
clear
C) Proportional to s done
clear
D) Proportional to \[1/s\] done
clear
E) A constant done
clear
View Solution play_arrow

question_answer64) The radius of a cylinder is increasing at the rate of 3 m/sec and its altitude is decreasing at the rate of 4m/sec. The rate of change of volume when radius is 4 meters and altitude is 6 meters is [Kerala (Engg.) 2005]
A) \[80\pi \,\]cu. m/sec done
clear
B) \[144\,\pi \,\]cu. m/sec done
clear
C) \[80\,\] cu. m/sec done
clear
D) \[64\,\] cu. m/sec done
clear
E) \[80\,\pi \] cu. m/sec done
clear
View Solution play_arrow

question_answer65) A ladder 10 m long rests against a vertical wall with the lower end on the horizontal ground. The lower end of the ladder is pulled along the ground away from the wall at the rate of 3 cm/sec. The height of the upper end while it is descending at the rate of 4 cm/sec is [Kerala(Engg.) 2005]
A) \[4\sqrt{3}\]m done
clear
B) \[5\sqrt{3}\]m done
clear
C) \[5\sqrt{2}\,m\] done
clear
D) 8 m done
clear
E) 6 m done
clear
View Solution play_arrow