While spinning down from 500 rpm to rest, a flywheel does of ...

[itsmyluck]

While spinning down from 500 rpm to rest, a flywheel does of work. This flywheel is in the shape of a solid uniform disk of radius 1.2 m. What is the mass of this flywheel?
 
  A) 4.0 kg
  B) 3.4 kg
  C) 4.6 kg
  D) 5.2 kg

Question 2

Which of the following processes is an example of an energy transformation from chemical energy to gravitational energy?
 
  A) burning coal to run an electric generator
  B) using the water behind a dam to run an electric generator
  C) a ball rolling downhill
  D) lifting a book, with your hands, from the floor to a table top
  E) striking lighting a match to warm up your hand

[micaelaswann]

Answer to Question 1

A

Answer to Question 2

D