Respuesta :
Answer:
The change in energy of the ball during its fall is 14.6 Joules.
Explanation:
Given that,
Mass of the ball, m = 25 g
It is released from rest 80 meters above the surface of the Earth, h = 80 m
Just before it hits the surface its speed is 20 m/s, v = 20 m/s
We need to find the change in energy of the ball during its fall. The potential energy gets converted to its kinetic energy. The change in energy is given by :
[tex]\Delta E=mgh-\dfrac{1}{2}mv^2\\\\\Delta E=25\times 10^{-3}\times 9.8\times 80-\dfrac{1}{2}\times 25\times 10^{-3}\times (20)^2\\\\\Delta E=14.6\ J[/tex]
So, the change in energy of the ball during its fall is 14.6 Joules.
Answer:
14.6 joule
Explanation:
mass of ball, m = 25 g = 0.025 kg
height, h = 80 m
speed at the time as the ball hits the ground, v = 20 m/s
Potential energy at the top, U = m g h
U = 0.025 x 9.8 x 80 = 19.6 Joule
Kinetic energy at the bottom, K = 0.5 x mv²
K = 0.5 x 0.025 x 20 x 20 = 5 Joule
Change in energy
E = Potential energy - Kinetic energy
E = 19.6 - 5 = 14.6 Joule
