Which of the following is not true about centripetal force? check all that apply.
a. centripetal force keeps a car on the road going around a curve.
b. without centripetal force, an object would continue in a straight line.
c. centripetal force is the same as gravity.
d. it's also called an inward force.
e. it's the same as centrifugal force.

Exercise 2. find the wavelength of a photon emitted when an electron jumps from the n = 3 energy level down to the n = 2 energy level. where is this photon in the electromagnetic spectrum?

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?

Frequency of electromagnetic waves that a radio station is assigned is called