Which two statements describe reasons that semiconductors must be included in a solar cell?
A. They form a zone of separation between the glass layer and the
terminal layer.
B. They provide a path through which released electrons move to
form an electric current.
c. They provide a path through which electrons exit the surface of
the cell and never return.
D. They provide a source of electrons to be released by the
photoelectric effect.

During which interval are the persons represented by the graph not moving? a) 0 to 0.5 hrs b) 1.5 to 2 hrs c) 2 to 2.5 hrs d) 4.5 to 5 hrs

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.

How much work would it take to move a coulomb charge across a 4 volt potential difference?