A train is moving at constant speed over a certain period of time. Which of the following statements about the train's motion during this period of time must be false? A. The magnitude of the train's velocity is constant.
B. The distance traveled by the train will be a positive, nonzero number.
C. The train's direction of motion may change.
D. The instantaneous speed may be higher or lower than the average speed.

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

How would a small bar magnet be oriented when placed at position x?

Which of the following is a measure of the amount of light a star directly emits?               a.  luminosity    b.  intensity    c.  wavelength    d.  brightness