A 2.0 kg mass starts from rest and slides down an inclined plane 8.0 x 10-1 m long in 0.50 s. What net force is acting on the mass along the incline?

What would the difference of spectral lines emitted by hydrogen gas in distant galaxies which is normally found at a wavelength of 21 cm on earth, be observed at 21.1 centimeters?

The passing of heat through a material while the material itself stays in place. a. radiation b. conduction c. convection

The solar panels used by mark function because of the photoelectric effect. light shines on the cells causing electrons to be ejected from the metal, which produces an electric current. at night on mars, no light will fall on the solar cells and no electric current will be generated. according to your notes, what type of light is typically needed to cause the photoelectric effect? a)visible b)ultraviolet c)infrared