Question

an object takes 5 second to reach the ground from height of 5 metre on a planet . what is value of g on planet​

Answer 1

Answer: Time taken, t = 5 seconds

Displacement, s = 5 metres

Initial velocity, u = 0 metres/second

Let the acceleration be a m/s2.

When the acceleration is constant, initial velocity, acceleration, time taken and displacement are related by a simple formula:

s=ut+(1/2)at2

Therefore,

5=(0)(5)+(1/2)(a)(52)

a×(25/2)=5

a=5/(25/2)

a=10/25

a=2/5

a=0.4

Therefore, the acceleration is 0.4m/s2.

This is the acceleration due to gravity on that planet.

Please note that you can't call ‘acceleration due to gravity’ as ‘gravity’.

Gravity refers to gravitational force. Gravitational force (gravity) due to the planet on any mass ‘m’ (expressed in kilograms) = (0.4×m) newtons.

Answer 2

Explanation: Relate and equate kinetic energy gained = potential energy lost.

mgh=1/2*mv square.

g=5m/s square.