Question

a cricket ball is dropped from a height of 40 m (1)calculate the speed of the ball when it hits the ground.(2) time it takes to fall through this height(10m/s^2)​

Answer 1

Answer:

mass of the ball it's not given in ur question

Answer 2

Question:

a cricket ball is dropped from a height of 40 m (1)calculate the speed of the ball when it hits the ground.(2) time it takes to fall through this height(10m/s^2)​

Given:

a cricket ball is dropped from a height of 40 m

To Find:

• The speed of the ball

• Time taken by the ball to fall through the height

Formulas Used:

• $v^2 = 2\times g \times h$

• $\sqrt{2gh}$

• $h = (\frac{1}{2})\times g \times t^2$

• $\sqrt{\frac{2h}{g}}$

Solution:

When the ball is dropped from height h, speed v of the ball when it reaches ground is calculated using the equation,  $v^2 = 2\times g \times h$

hence speed v =

 $\sqrt{2gh} \\\\\\=\sqrt{2\times 9.8\times40} \\\\\\=20m/s^2$

Time taken t to reach the ground is obtained using the equation " $h = (\frac{1}{2})\times g \times t^2$

hence time taken t to reach ground  =  

$=\sqrt{\frac{2h}{g}} \\\\\\=\sqrt{\frac{2\times 40 }{9.8}}\\\\\\=\sqrt{\frac{80}{9.8}}\\\\\\=8.1 seconds$

Answers:

• 20m/s²

• 8.1 seconds