What happens to the sum of the ball’s kinetic energy and potential energy as the ball rolls from point a to point e? assume there’s no friction between the ball and the ground. the sum decreases. the sum increases. the sum remains the same. the sum always equals zero.

Acoil formed by wrapping 80 turns of wire in the shape of a square is positioned in a magnetic field so that the normal to the plane of the coil makes an angle of 28.0° with the direction of the field. when the magnetic field is increased uniformly from 200 µt to 600 µt in 0.400 as, an emf of magnitude 80.0 mv is induced in the coil. what is the total length of the wire?

Ais not a compound machine. a. bolt b. shovel c. handcart (dolly) d. see-saw (teeter totter)

Light from the sun reaches the earth in 8.3 minutes. the velocity is 3.00 x 10^8 m/s. how far is earth from the sun? i know how to get to d = (3 x 10^8 m/s)(498 sec). i just don't know how to get from there to the answer being 1.5 x 10^11 m.