Question

A stone dropped off a tall building. It takes 5.3s to hit the ground. determine the height of the building

Answer 1

Answer:

stone is dropped so initial velocity u= 0

it is case of free fall

we know,

v^2= u^2 + 2gs

here u= 0

so that, v= √2gh

v = u + at

√2gh= g * 5.3

square on both sides..

2gh = g^2 * 28.09

h= 140.45 m

Answer 2

Dear student,

Given :-

• initial velocity, u = 0
• time taken, t = 5.3 seconds
• acceleration, a = g = 10 m/s²

To find :-

• determine the height of the building

Solution :-

We know by the Newtonian Equations for motion that :

s = ut + 1/2 at²

Putting the given values in the formula, we obtain :

h = 0(5.3) + 1/2 × 10 × (5.3)²

h = 1/2 × 10 × 5.3 × 5.3

h = 5 × 5.3 × 5.3

h = 140.45 m

Hence the height of the building is 140.45 m.