Question

A stone is dropped from the top of a cliff. It is seen to hit the ground below after 3.50 s. How high is the cliff?​

Answer 1

Answer:

Given :-

• A stone is dropped from the top of a cliff.
• It is seen to hit the ground below after 3.50 seconds.

To Find :-

• How high is the cliff.

Formula Used :-

$\clubsuit$ Time Taken Formula :

$\bigstar \: \: \sf\boxed{\bold{\pink{T =\: \sqrt{\dfrac{2h}{g}}}}}\: \: \: \bigstar$

where,

• T = Time Taken
• h = Height
• g = Acceleration due to gravity

Solution :-

Given :

• Time taken = 3.50 seconds
• Acceleration due to gravity = 9.8 m/s²

According to the question by using the formula we get,

$\implies \sf\bold{\purple{T =\: \sqrt{\dfrac{2h}{g}}}}$

$\implies \sf 3.50 =\: \sqrt{\dfrac{2h}{9.8}}$

$\implies \sf (3.50)^2 =\: \dfrac{2h}{9.8}$

$\implies \sf 3.50 \times 3.50 =\: \dfrac{2h}{9.8}$

$\implies \sf 12.25 =\: \dfrac{2h}{9.8}$

By doing cross multiplication we get,

$\implies \sf 2h =\: 9.8 \times 12.25$

$\implies \sf 2h =\: 120.05$

$\implies \sf h =\: \dfrac{120.05}{2}$

$\implies \sf\bold{\red{h =\: 60.025\: m}}$

$\therefore$ The height of the cliff is 60.025 m .