How much work does gravity do on a 0.120-kg ball falling from a height of 17.0 m?
What is the kinetic energy of a 25 kg dog that is running at a speed of 8.9 m/s (about 20 mi/h)?
To find the amount of work gravity does on the ball, we need to use the formula for work:
Work = Force * Distance * Cosine(theta)
In this case, the force is the force of gravity acting on the ball, which can be calculated using the formula:
Force = mass * acceleration due to gravity
The acceleration due to gravity is approximately 9.8 m/s^2.
So, the force of gravity acting on the ball is:
Force = 0.120 kg * 9.8 m/s^2 = 1.176 N
Now, we need to find the distance the ball falls, which is given as 17.0 m.
Finally, the angle theta is the angle between the force and the direction of motion. In this case, since the force of gravity is acting downward, and the ball is falling straight down, theta is 0 degrees.
Cosine(0) = 1, so we can ignore the cosine term in this case.
Now, we can calculate the work done by gravity:
Work = Force * Distance = 1.176 N * 17.0 m = 19.992 J
Therefore, the amount of work gravity does on the ball is 19.992 Joules.
1. W =mgh
2. KE= mv²/2