Physics - Description of Motion in One Dimension

Question - 1

A stone is dropped from an ascending balloon moving with velocity \(\vartheta \) at a height H.  The stone will

  • A move vertical distance of \(({{\vartheta^{2} \over g}+H})\)
  • B cover a total vertical distance of \(({{\vartheta^{2} \over 2g}+H})\)
  • C move along a parabolic path and cover a total vertical distance of \(({{\vartheta^{2} \over g}+H})\).
  • D mover vertically down and cover a distance H.

Question - 2

Two bodies move along two perpendicular tracks at 21.6 km \(h^{-1}\).  The relative velocity of one with respect to the other will be

  • A 8.5 m \(s^{-1}\)
  • B 6.5 m \(s^{-1}\)
  • C 3.5 m \(s^{-1}\)
  • D None of the above

Question - 3

A ball is thrown vertically upwards with a certain speed \(\vartheta \) and is received by the thrower in 4 s.

  • A Its average speed is zero.
  • B Its average speed is \(\vartheta \).
  • C Its average velocity is 9.8 \(\times\) 4 m \(s^{-1}\)
  • D Its average velocity is always zero.

Question - 4

With the usual notation, for a uniformly retarded body

  • A the formula s = \(\vartheta \)t+\(1\over2\)\(at^{2}\) holds good
  • B the formula s = ut+\(1\over2\)\(at^{2}\) holds good
  • C the formula \(\vartheta \) = u + at holds good
  • D the formula s = \(\vartheta \)t - \(1\over2\)\(at^{2}\)  holds good

Question - 5

A body which is uniformly accelerated changes its velocity from 20 m \(s^{-1}\) to 10 m \(s^{-1}\) in 5 secounds while moving in the opposite direction.  The total distance travelled in 5 s is ......... and the total displacement is .........

  • A \(25\over3\)m and \(125\over3\)m
  • B \(100\over3\)m and \(75\over3\)m
  • C \(125\over3\)m and \(75\over3\)m
  • D \(75\over3\)m and \(25\over3\)m

Question - 6

A rocket is to be projected vertically upwards.  It is fired with net acceleration '2g'  where is acceleration due to gravity.  After 2 minites, the fuel is exhausted.  After the fuel is exhausted, the time taken by the rocket to reach the highest point is

  • A 1 minute
  • B 2 minute
  • C 4 minute
  • D 8 minute

Question - 7

The displacement x of a particle moving on x-axis at any time t is given by the equation.
4t = 25 \(^{+}_{-}\sqrt{100-x}\)
The acceleration of the particle is

  • A constant and equal to 16 m \(s^{-1}\) along negative x-axis
  • B constant and equal to 32 m \(s^{-1}\) along negative x-axis
  • C constant and equal to 32 m \(s^{-1}\) along positive X-direction
  • D not constant and acts along positive as well as negative X-direction depending on the magnitude of displacement x.

Question - 8

A tennis ball is dropped on the floor from a height of 1 m.  It rebounds to a height of 0.5 m.  If the ball was in contact with the floor for 0.01 s, the average acceleration during contact in the upward direction is

  • A zero
  • B 129 m \(s^{-2}\)
  • C 442 m \(s^{-2}\)
  • D 775 m \(s^{-2}\)

Question - 9

Choose the incorrect statement

  • A A body can have zero velocity and finite acceleration
  • B A body can have a constant velocity but a varying speed
  • C A body can have a constant speed but a varying velocity
  • D The direction of the velocity of a body can change when its acceleration is constant.

Question - 10

A particle moves along the X-axis such that its coordinate (x) varies with time (t) according to the expression
x = 2 - 5 t - 6 \(t^{2}\)
where x is in meters and t is in seconds. The initial velocity of the particle is

  • A - 5 m \(s^{-1}\)
  • B - 3 m \(s^{-1}\)
  • C 6 m \(s^{-1}\)
  • D 2 m \(s^{-1}\)