Home
Class 11
PHYSICS
A body falls freely from a height of 125...

A body falls freely from a height of 125m `(g = 10 m//s^2)` after 2 sec gravity ceases to act Find the time taken by it to reach the ground?

Text Solution

Verified by Experts

Distance covered in 2s under gravity
`s_(1)=1/2 gt^(2)=1/2 (10) (2^(2))=20m`
velocity at the end of 2s, V=gt =(10)2=20m/s.
Now at this instant gravity ceases to act a velocity by here after becomes constant
The remaining distance which is 125-20=105 m is covered by the body with constant velocity of 20 m/s.
Time taken to cover 105 m with constant velocity is given by `t_1=S/V rArr t_(1)=(105)/(20)=5.25s`
Henee total time taken to reach the ground
=2+5.25 =7.25s
Promotional Banner

Similar Questions

Explore conceptually related problems

A body falls freely from a height 'h' after two seconds if accelaration due to gravity is reversed the body

A balloon starts rising from the ground with a constant acceleration of 1.25m//s^(2) . After 8 s, a stone is released from the balloon. Find the time taken by the stone to reach the ground. (Take g=10m//s^(2) )

A body falls freely from a height 'h' after two seconds if we assume that gravity disappears the body

A bullet is projected upwards from the top of a tower of height 90 m with the velocity 30 ms^(-1) making an angle 30^(@) with the horizontal. Find the time taken by it to reach the ground is (g=10 ms^(-2))

A balloon rises with uniform velocity of 10 ms^(-1) . When the balloon is at a height of 75 m if a stone is dropped from it the time taken by it to reach the ground is

A body is dropped from a height 135 m. If after 3 sec acceleration due to gravity of earth cases to act then the further time of descent is (g=10 "m/s"^2)

Body 1 of mass M is dropped from a height of 1 m and body 2 of mass 3 M is dropped from a height of 9 m. Ratio of time taken by bodies 1 and 2 to reach the ground is

A balloon starts rising from the ground with an acceleration of 1.25 m//s^(2) . A stone is released from the balloon after 10s. Determine (1) maximum height of ston from ground (2) time taken by stone to reach the ground

A body falls for 4s from rest. If the acceleration due to gravity of earth ceases to act, then the velocity and distance it travels in the next 3sec is

A football ils kicked with a velocity of 20 m/s at an angle of 45^0 wilth the horizontal. A. Find the time taken by the ball to strike the ground. b.Find the maximum height it reaches. C. How far away from the kick dows it hit the ground? Take g=10 m/s^2 .