Why won't a very bright beam of red light impart more energy to an ejected electron than a feeble beam of violet light?

What are the factors that affect the resistance of a wire?

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?

Which of the following is the main energy source for the sun? a. fission of hydrogen b. fusion of hydrogen c. fusion of helium d. fission of iron