What is the speed of a proton whose kinetic energy is 3.4 kev ?

Name three different units of energy used to measure heat and describe what type of situations each is usually used.

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.

What is the coefficient of kinetic friction μk between the block and the tabletop?