Calculate the potential energy of an object with a mass of 15 kg while sitting on a shelf that his 20 m high

Aphoton is absorbed by an electron that is in the n = 3 state of a hydrogen atom, causing the hydrogen atom to become ionized. very far away from the nucleus, the released electron has a velocity of 750,000 m/s. what was the wavelength of the absorbed photon?

Four identical lab carts each have a mass of 200 kg. different masses are added to the carts and the velocities are measured. all carts move to the right.

The diagram shows a wave. the quantity shown is the amplitude. this quantity is directly proportional to which of these other quantities? a) energy b) frequency c) period d) wavelength