Consider a coin which is tossed straight up into the air. After it is released it moves upward, reaches its highest point and falls back down again. While the coin is moving upward after being released, what would be its acceleration?
Take up to be the positive direction.
1. The acceleration is in the negative direc-
tion and increasing.
2. The acceleration is in the negative direc-
tion and decreasing
3. The acceleration is in the negative direc-
tion and constant.
4. The acceleration is in the positive direc-
tion and increasing.
5. The acceleration is in the positive direc-
tion and decreasing.
6. The acceleration is zero.
7. The acceleration is in the positive direc-
tion and constant.

1. what is the relationship between wavelength and the penetrating power of an electromagnetic wave? a) the penetrating power has no relationship to the wavelength. b) the penetrating power increases as the wavelength increases. c) the penetrating power decreases as the wavelength increases. d) the penetrating power decreases as the wavelength decreases. 2. as ice melts and turns into water, the speed of sound through the material would most likely do what? justify your answer. a) the speed would not change because the material is always water. b) the speed of sound would increase because the density of water is less than that of ice. c) the speed of sound would increase because energy is added to ice in order to make it melt. d) the speed of sound would decrease because sound travels faster through solids than liquids. 3.which of these waves need a medium to travel through? a) sound b) x-rays c) infrared rays d) visible light