Question

A stone dropped from the top of building is free fall for 8sec calculate;a.its velocity when it reaches the ground. b. the height of the building from which the stone dropped.​

Answer 1

The velocity of the stone when it reaches the ground is 78.4 m/s. The height of the building from which the stone dropped is 313.6 m.

Step-by-step explanation:

To calculate the velocity of the stone when it reaches the ground, we can use the equation v = gt, where v is the final velocity, g is the acceleration due to gravity (approximately 9.8 m/s²), and t is the time the stone is in free fall (8 seconds in this case). Therefore, v = 9.8 m/s² * 8 s = 78.4 m/s.

To find the height of the building from which the stone dropped, we can use the equation h = (1/2)gt², where h is the height, g is the acceleration due to gravity, and t is the time the stone is in free fall. Plugging in the values, h = (1/2) * 9.8 m/s² * (8 s)² = 313.6 m.

Answer 2

Step-by-step explanation:

a. To calculate the velocity of the stone when it reaches the ground, we can use the formula:

v = u + gt

Where:

v = final velocity (unknown)

u = initial velocity (0 m/s as the stone is dropped)

g = acceleration due to gravity (approximately 9.8 m/s²)

t = time in seconds (8 sec)

Plugging in the values:

v = 0 + 9.8 * 8

v = 78.4 m/s

Therefore, the velocity of the stone when it reaches the ground is 78.4 m/s.

b. To calculate the height of the building from which the stone was dropped, we can use the formula:

s = ut + (1/2)gt²

Where:

s = distance or height (unknown)

u = initial velocity (0 m/s as the stone is dropped)

g = acceleration due to gravity (approximately 9.8 m/s²)

t = time in seconds (8 sec)

Plugging in the values:

s = 0 * 8 + (1/2) * 9.8 * (8²)

s = 0 + 0.5 * 9.8 * 64

s = 0 + 313.6

s = 313.6 meters

Therefore, the height of the building from which the stone was dropped is 313.6 meters.