Along cylindrical shell (radius = 2.0 cm) has a charge uniformly distributed on its surface. if the magnitude of the electric field at a point 8.0 cm radially outward from the axis of the shell is 85 n/c, how much charge is distributed on a 2.0-m length of the charged cylindrical surface? the answer is suppose to be 0.76nc, i just don't know how to get there. explain

Abaseball has a mass of 0.145 kg and approaches a bat at 40.0 m/s. after it is hit, the ball leaves the bat at 50.0 m/s directly back. find the impulse of the bat on the ball. 7.25 kg*m/s 13.1 kg*m/s 5.80 kg*m/s 1.45 kg*m/s

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?