A car starting from rest accelerates at the rate f through a distance S, then continues at constant speed for time t and then decelerates at the rate f/2 to come to rest. If the total distance traversed is 15 S, then
S=ft
S= ft2/72
S = 1/2 ft2
S = 1/2 ft2
B.
S= ft2/72
A parachutist after bailing outfalls 50 m without friction. When a parachute opens, it decelerates at 2 m/s2. He reaches the ground with a speed of 3 m/s. At what height, did he bail out?
91 m
182 m
293 m
293 m
C.
293 m
A particle is moving eastwards with a velocity of 5 m/s in 10 seconds the velocity changes to 5 m/s northwards. The average acceleration in this time is
zero
zero
D.
zero
A particle located at x = 0 at time t = 0, starts moving along the positive x-direction with a velocity ‘v’ that varies as v= α√x . The displacement of the particle varies with time as
t3
t2
t
t
B.
t2