Equations of Motion

A stone is thrown vertically upwards. On its way, passes a point (P) with a speed (v) and point (Q) is (20 m) higher than (P) with a speed $\frac{\sqrt{5}}{3}v$ . The value of (v) is … ( $g=10\ m/s^2$ )

•  $20\sqrt{5}\ m⁄s$ 

•  $15\sqrt{5}\ m⁄s$ 

•  $25\ m⁄s$  

•  $30\ m⁄s$  

A stone is dropped from the top of the tower. Its speed after it has fallen 20 m is…. $(g=10\ ms^{-2})$ 

•  $-10\ ms^{-1}$  

•  $10\ ms^{-1}$  

•  $-20\ ms^{-1}$  

•  $20\ ms^{-1}$  

A particle starts its motion from rest with constant acceleration. If the distance covered in first 10 seconds is $d_1$  and that covered in the first 20 seconds is $d_2$ , then …

•  $d_2=d_1$  

•  $d_2=2d_1$  

•  $d_2=3d_1$  

•  $d_2=4d_1$  

An aircraft is flying at a height of  above the ground. If the angle subtended at a ground observation point by the aircraft positions  apart is $30\degree$ , then the speed of the aircraft is …

•  $10.8\ ms^{-1}$ 

•  $1963\ ms^{-1}$ 

•  $108\ ms^{-1}$  

•  $196.3\ ms^{-1}$  

A body moving along the positive x-axis with uniform acceleration of ( $-4\ m.s^{-2}$ ). Its velocity at ( $x=0$ ) is ( $10\ m.s^{-1}$ ). The time taken by the body to reach a point at ( $x=12\ cm$ ) is …

• 2 s   

•  0.25 s 

• 3 s 

• 0.0125 s

The figure represents a ball falling freely from a height (H) above the ground. It takes 2s to reach midway to ground (H). What is the required time for the ball to cover the other half distance to the ground? Given that: ( $g=10\ m/s^2$  )

•  $3.0\ s$  

•  $2.0\ s$  

•  $0.83\ s$  

•  $0.5\ s$  

A stone and a ball are projected upwards at the same time, where the stone is projected at 20m/s while the ball at 10m/s. If the maximum height reached by the ball is (H), What is the maximum height reached by the stone? (neglecting air resistance against the movement of stone and ball)

• $½H$

• $H$

• $2H$

• $4H$

A ball moving with an initial velocity of 100 m/s north is given an acceleration of 10 m/s² south. What will its velocity be after 6.0 s?

• 60 m/s north

• 40 m/s north

• 40 m/s south

• 60 m/s south

An object is dropped from rest and falls freely 20 meters to the Earth. When is the speed of the object 9.8 meters per second?

• During the entire first second

• At the end of its first second of fall

• During its entire time of fall

• After it has fallen 9.8 meters

A book of mass (m) falls freely from rest to the floor from the top of desk of height (h). What is the speed of the book upon striking the floor?

•  $\sqrt{2gh}$  

•  $2gh$  

•  $mgh$  

•  $mh$