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 projectile can have the same range R for two angles of projection. If t1 and t2 be the times of flights in the two cases, then the product of the two time of flights is proportional to
R2
1/R2
1/R
1/R
D.
1/R
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
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