Use g=10 N/kg in this assignment.
1. What is the gravitational energy (relative to the unstretched surface of the trampoline) of the 20 kg ball at its apex 2 m above the trampoline?
I got 400 J
2. What is the kinetic energy of the ball just before impacting the trampoline?
I got 0 J
3. At maximum stretch at the bottom of the motion, what is the sum of the elastic and gravitational energy of the ball?
Is it because the sum of elastic and potential energy is equal to the change in gravitational energy from original position?
4. What conclusions can be drawn from the answers above
I'm not too sure what to put as my answer
To find the answers, let's break down each question and explain how to get the answers:
1. What is the gravitational energy (relative to the unstretched surface of the trampoline) of the 20 kg ball at its apex 2 m above the trampoline?
Gravitational energy, also known as potential energy, is given by the equation: potential energy = mass * gravity * height.
Plugging in the given values: potential energy = 20 kg * 10 N/kg * 2 m = 400 J.
2. What is the kinetic energy of the ball just before impacting the trampoline?
Kinetic energy is given by the equation: kinetic energy = 1/2 * mass * velocity^2. Since the question doesn't provide the velocity, it's safe to assume that the velocity is 0 right before impact. Therefore, the kinetic energy would be 0 J.
3. At maximum stretch at the bottom of the motion, what is the sum of the elastic and gravitational energy of the ball?
To answer this question, you need to understand that at the apex of the motion, all the gravitational potential energy will be converted to elastic potential energy as the trampoline stretches. So, at the bottom of the motion, the elastic potential energy is equal to the change in gravitational energy from the original position. Thus, the sum of the elastic and gravitational energy is equal to the 400 J from the previous question.
4. What conclusions can be drawn from the answers above?
Based on the answers, we can deduce that at the apex, the ball has 400 J of gravitational energy (potential energy) due to its position above the trampoline. Just before impact, the ball has no kinetic energy, as its velocity is 0. And at the bottom of the motion, the sum of the elastic and gravitational energy is still 400 J. This suggests that energy is conserved throughout the motion, with the potential energy being converted into elastic energy and back again.