Acommon carnival ride, called a gravitron, is a large r = 11 m cylinder in which people stand against the outer wall. the cylinder spins so that the riders move with a linear speed v. at a certain point the floor of the cylinder lowers and the people are surprised they don't slide down. the friction between the wall and their clothes is μs = 0.62. what is the minimum speed, in meters per second, that the cylinder must make a person move at to ensure they will "stick" to the wall?

Astudent is performing an experiment comparing sound and light waves. the student gathers the following data. what conclusion does the student most likely make based on this data? light waves always travel the same speed; however, the speed of sound is determined by the medium that it travels through. all sound waves always have the same energy, so the temperature of the medium does not affect wave speed. light needs to vibrate particles, so it travels fastest in tightly packed solids, while sound does not need a medium, so it travels fastest in a gas. tightly packed particles in solids slow down the light waves; however, sound waves make particles bounce into each other, so they travel faster in solids.

Light traveling in a medium with a refractive index 1.19 is incident on a plate of another medium with index of refraction 1.79. at what angle of incidence is the reflected light fully polarized?

Amoving electron has kinetic energy k1. after a net amount of work w has been done on it, the electron is moving one-quarter as fast in the opposite direction. (a) find w in terms of k1. (b) does your answer depend on the final direction of the electron's motion?