Aperson twirls a key chain in a circle. if she twirls it faster, she finds that she holds the chain tighter. explain why this is necessary.

Which lists the fundamental forces in order, from strongest to weakest? strong nuclear, weak nuclear, electromagnetic, gravitational strong nuclear, electromagnetic, weak nuclear, gravitational gravitational, weak nuclear, electromagnetic, strong nuclear electromagnetic, gravitational, strong nuclear, weak nuclear

Apulley with mass mp and a radius rp is attached to the ceiling, in a gravity field of 9.81 m/s2 and rotates with no friction about its pivot.

The nuclear potential that binds protons and neutrons in the nucleus of an atom is often approximated by a square well. imagine a proton conned in an innite square well of length 105 nm, a typical nuclear diameter. calculate the wavelength and energy associated with the photon that is emitted when the proton undergoes a transition from the rst excited state (n 2) to the ground state (n 1). in what region of the electromagnetic spectrum does this wavelength belong?