9th Class Science Gravitation and Floatation Question Bank

done Gravitation IIT JEE Objective Problems Total Questions - 16

• question_answer1)
  The mass of the Earth is 80 times the mass of a planet and diameter is twice that of the planet. Then the acceleration due to gravity on the planet's surface is
  A)
   \[0.\text{49m}/{{\text{s}}^{\text{2}}}\]        done clear
  B)
   \[\text{9}.\text{8m}/{{\text{s}}^{\text{2}}}\] done clear
  C)
   \[\text{1}.\text{6 m}/{{\text{s}}^{\text{2}}}\]                   done clear
  D)
   \[0.\text{8m}/{{\text{s}}^{\text{2}}}\] done clear
  View Solution play_arrow

• question_answer2)
  If the weight of an object when measured inside a coal mine, at the sea level and on the top of a mountain is found to be\[{{w}_{1}},{{w}_{2}}\]and\[{{w}_{3}}\] respectively, then
  A)
   \[{{W}_{1}}>{{W}_{2}}>{{W}_{3}}\]        done clear
  B)
   \[{{W}_{1}}={{W}_{2}}={{W}_{3}}\] done clear
  C)
   \[{{W}_{1}}<{{W}_{2}}>{{W}_{3}}\]     done clear
  D)
   \[{{W}_{1}}>{{W}_{2}}<{{W}_{3}}\] done clear
  View Solution play_arrow

• question_answer3)
  Acceleration due to gravity is g on the surface of the Earth. Then the value of the acceleration due to gravity at a height of 32 km above Earth's surface is (Radius of the Earth = 6400 km)
  A)
   0.99 g                   done clear
  B)
   0.8 g    done clear
  C)
   1.01 g                                   done clear
  D)
   0.9 g done clear
  View Solution play_arrow

• question_answer4)
  A body is thrown vertically upwards with an initial velocity u reaches a maximum height in 6s. The ratio of the distance travelled by the body in the first second to the seventh second is
  A)
   1 : 1                       done clear
  B)
   11 : 1   done clear
  C)
   1 : 2                       done clear
  D)
   1 : 11 done clear
  View Solution play_arrow

• question_answer5)
  A person standing on the edge of a well throws a stone vertically upwards with an initial velocity \[5\,\,m{{s}^{-1}}.\]The stone gone up, comes down and falls in the well making a sound. If the person hears the sound 3 second after throwing, then the depth of water (neglect time travel for the sound and take \[g=10m{{s}^{-2}}\])
  A)
   1.25 m                  done clear
  B)
   21.25 m   done clear
  C)
   30 m     done clear
  D)
   32.5 m done clear
  View Solution play_arrow

• question_answer6)
  A stone thrown vertically up from the ground reaches a maximum height of 50m in 10s. Time taken by the stone to reach the ground from maximum height is
  A)
   5s                                           done clear
  B)
   10s   done clear
  C)
   20s                        done clear
  D)
   25s done clear
  View Solution play_arrow

• question_answer7)
  A body thrown up with some initial velocity reaches a maximum height of 50m. Another body with double the mass thrown up with double the initial velocity will reach a maximum height of
  A)
   100 m                   done clear
  B)
   200 m done clear
  C)
   400 m                   done clear
  D)
   50 m done clear
  View Solution play_arrow

• question_answer8)
  A ball is thrown vertically upwards with a speed of 10 m/s from the top of the tower 200m high and another is thrown vertically downwards with the same speed simultaneously. The time difference between them in reaching the ground is (\[\text{g}=\text{1}0\text{ m}/{{\text{s}}^{\text{2}}}\])
  A)
   12s                        done clear
  B)
   6s    done clear
  C)
   2s                           done clear
  D)
   1s done clear
  View Solution play_arrow

• question_answer9)
  A wooden block of mass 10 gm is dropped from the top of a cliff 100 m high. Simultaneously a bullet of mass 10 gm is fired from the foot of the cliff upward with a velocity 100 m/s. The bullet and the wooden block will meet each other after a time of
  A)
   10 s                       done clear
  B)
   0.5 s   done clear
  C)
   1 s    done clear
  D)
   7 s done clear
  View Solution play_arrow

• question_answer10)
  A body sliding on a smooth inclined plane requires 4s to reach the bottom starting from rest at the top. Time taken by it to cover one fourth of the distance starting from rest at the top is
  A)
   1 s                          done clear
  B)
   2 s    done clear
  C)
   4 s                          done clear
  D)
   16 s done clear
  View Solution play_arrow

• question_answer11)
  Two bodies of different masses\[{{m}_{a}}\] and\[{{m}_{b}}\] are dropped from two different heights viz a and b. Ratio of times taken by the two, to drop through these distances is
  A)
   a : b                                       done clear
  B)
   \[\sqrt{b}:\sqrt{a}\]   done clear
  C)
   \[\sqrt{a}:\sqrt{b}\]       done clear
  D)
   \[{{a}^{2}}:{{b}^{2}}\] done clear
  View Solution play_arrow

• question_answer12)
  A body let fall from the top of a building reaches the ground in 3 s. Height of the building is
  A)
   14.7 m                  done clear
  B)
   24.4 m done clear
  C)
   44.1 m done clear
  D)
   66.2 m done clear
  View Solution play_arrow

• question_answer13)
  A ball released from a height h touches the ground in t sec. After t/2 s since dropping, the height of the body from the ground
  A)
   h/2                        done clear
  B)
   h/4    done clear
  C)
   3h/4 done clear
  D)
   Depends upon mass and volume of ball. done clear
  View Solution play_arrow

• question_answer14)
  A body throws balls vertically upwards. He throws one, while the previous one is at its highest point. Maximum height reached by a ball if he throws one ball each per second at uniform speed is
  A)
   19.6 m                  done clear
  B)
   9.8 m done clear
  C)
   4.9 m    done clear
  D)
   2.45 m done clear
  View Solution play_arrow

• question_answer15)
  A bullet is fired horizontally with a velocity 400 m/s from the top of a tower. At the same time a stone is dropped from the same point. Then
  A)
   Stone will reach the ground first done clear
  B)
   Bullet will reach the ground first done clear
  C)
   Both will reach the ground at same time done clear
  D)
   Their times of fall depend on g done clear
  View Solution play_arrow

• question_answer16)
  Taking that Earth revolves round the Sun in a circular orbit of radius\[1.5\times {{10}^{10}}m\]. with a time period of 1 year, the time taken by another planet, which is at a distance of \[\text{54}0\times \text{1}{{0}^{\text{1}0}}\text{ m}\], to revolve round the Sun in circular orbit once will be
  A)
   216 yrs                 done clear
  B)
   144 yrs done clear
  C)
   72 yrs                   done clear
  D)
   36 yrs done clear
  View Solution play_arrow