Which statement describes the motion of a ball as it drops onto a vertical spring? a. The acceleration of the ball decreases as the spring shrinks.
b. The accIleration of the ball decreases as the spring extends.
c. The velocity of the ball changes from positive to negative as the spring shrinks.
d. The velocity of the ball changes from negative to positive as the spring extends.

Agymnast dismounts off the uneven bars in a tuck position with a radius of 0.3m (assume she is a solid sphere) and an angular velocity of 2rev/s. during the dismount she stretches out into the straight position, with a length of 1.5m, (assume she is a uniform rod through the center) for her landing. the gymnast has a mass of 50kg. what is her angular velocity in the straight position?

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

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