Question

An object takes 10 seconds to reach the ground from a height of 25 m on a planet what is the value of 'g'on the planet

Answer 1

Given :

Height of the building = 25 m

Time taken to reach the ground = 10s

To Find :

Value of g on that planet.

Solution :

❒ For a body falling freely under the action of gravity, g is taken positive.

In this case, constant acceleration due to gravity acts on object throughout motion$.$

We can apply equation of kinematics when acceleration has constant magnitude.

Let's apply second equation of kinematics,

➙ H = ut + 1/2 gt²

For free falling object, u = 0

➙ H = 1/2 gt²

• H denotes height
• g denotes acceleration
• t denotes time

By substituting the given values;

➙ 25 = 1/2 g (10)²

➙ 100g = 25 × 2

➙ 100g = 50

➙ g = 50/100

➙ g = 1/2

➙ g = 0.5 m/s²