A ball is dropped from a high rise platform at t=0 starting from rest. After 6s another ball is thrown downwards from the same platform with a speed v. The two balls meet at t=18 s. What is the value of v? (take g=10 )
1. 2.
3. 4.
A particle moves a distance x in time t according to equation The acceleration of the particle is proportional to,
1.
2.
3.
4.
A bus is moving with a speed of \(10~\text{ms}^{-1}\) on a straight road. A scooterist wishes to overtake the bus in \(100~\text{s}\). If the bus is at a distance of \(1~\text{km}\) from the scooterist, with what minimum speed should the scooterist chase the bus?
1. \(20~\text{ms}^{-1}\)
2. \(40~\text{ms}^{-1}\)
3. \(25~\text{ms}^{-1}\)
4. \(10~\text{ms}^{-1}\)
A particle starts its motion from rest under the action of a constant force. If the distance covered in first 10 s is and that covered in the first 20 s is then
1.
2.
3.
4.
The distance travelled by a particle starting from rest and moving with an acceleration in the third second is
1. 6m
2. 4m
3.
4.
A particle shows a distance-time curve as given in this figure. The maximum instantaneous velocity of the particle is around the point:
1. B
2. C
3. D
4. A
A particle moves in a straight line with a constant acceleration. It changes its velocity from 10 to while passing through a distance of 135 m in t seconds. The value of t is:
1. 10
2. 1.8
3. 12
4. 9
A particle covers half of its total distance with speed and the rest half distance with speed Its average speed during the complete journey is
(1)
(2)
(3)
(4)
A boy standing at the top of a tower of \(20\) m height drops a stone. Assuming \(g=10\) m/s2, the velocity with which it hits the ground will be:
1. \(20\) m/s
2. \(40\) m/s
3. \(5\) m/s
4. \(10\) m/s
The motion of a particle along a straight line is described by the equation; \(x=8+12 t-t^3,\) where \(x\) is in metre and \(t\) is in second. The retardation of the particle when its velocity becomes zero is:
1. | \(24 ~\text{ms}^{-2} \) | 2. | zero |
3. | \( 6 ~\text{ms}^{-2} \) | 4. | \(12 ~\text{ms}^{-2} \) |