using the polar coordinate, The cross section of a ring is (essentially) a little rectangle with side lengths dr and rdθ, as shown in Fig.1.13. How is the cross section of a ring a rectangle?​

What is the momentum of a 2 kg object moving at 15 meters per second

When the displacement of a mass on a spring is 12a the half of the amplitude, what fraction of the mechanical energy is kinetic energy? at what displacement, as a fraction of a, is the mechanical energy half kinetic and half potential?

What accounts for an increase in the temperature of a gas that is kept at constant volume? a. energy has been removed as heat from the gas. b. energy has been added as heat to the gas. c. energy has been removed as work done by the gas. d. energy has been added as work done by the gas.