What force makes a marble roll across level ground eventually come to a stop?

When you turn on a battery-operated device, an electrical circuit is

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.

Ryan is examining the energy of the particles in a bar of gold. what is ryan most likely studying?