Author Question: A hoop and a solid disk both have the same radius and mass and negligible thickness. Assume that ... (Read 127 times)

WhattoUnderstand · **on:** Jul 28, 2018

A hoop and a solid disk both have the same radius and mass and negligible thickness. Assume that they are both rotating with the same constant angular speed. Which has the higher rotational kinetic energy?
1.the hoop
2.the disk
3.They both have the same rotational kinetic energy.
4.impossible to determine

Question 2

You can determine the mass of the Moon
1.by measuring how long it takes to revolve around the Earth.
2.by measuring its distance from the Earth.
3.by measuring its diameter as well as the rate at which objects accelerate due to gravity on the Moon.
4.by doing any of these.