How many excess electrons must be distributed uniformly within the volume of an isolated plastic sphere 28.0 cmcm in diameter to produce an electric field of 1050 N/CN/C just outside the surface of the sphere?

Starting with only the balmer series light (visible light), how could we ensure that the solar panels generate a current that mark can use for his power station? a)by gradually increasing the brightness (amount) of light that we shine on it. b)by gradually increasing the frequency of the light we shine on it. c)by gradually increasing the wavelength of the light that we shine on it.

Debbie places two shopping carts in a cart corral she pushes the first cart which then pushes a second cart what force is being exerted

Cathy is pedaling down a steep hill on her bicycle and wants to be able to coast up the next hill, which is 25 meters high, without pedaling. cathy and her bicycle have a mass of 75 kg. assuming her bicycle is 100% efficient, what would her speed have to be?