If each metal is hit with light at a minimum wavelength, can I vary the intensity of the light to start emitting electrons?

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?

Balloon a has charge q, and identical mass balloon b has charge 10q. you hang them from threads near each other. choose all of the statements with which you agree. check all that apply. a. a and b exert the same magnitude forces on each other. b. the force that a exerts on b is 10 times the force that b exerts on a. c. the angle between the thread supporting a and the vertical is < the angle between the thread supporting b and the vertical. d. the force that a exerts on b is 1/10 the force that b exerts on a.