A piece of wood is floating in a bathtub. A second piece of wood sits on top of the first piece, and does not touch the water. I
f the top piece is taken off and placed in the water, what happens to the water level in the tub? A. The water level cannot be determined without additional information.B. The water level remains unchanged.C. The water level rises.D. The water level drops.
The first thing to realize is that the buoyancy force is the same as, or equal to the weight of the wood, this same force is also the same as or equal to the weight of the water displaced by the wood. In the two cases, the weight of the wood will be unaffected nonetheless, and thus the water level will remain the same.
Therefore, the answer is B, the water level remains unchanged.
Therefore, light travelling at 3.0x10^8 meters per second takes 500 seconds (8 minutes, 20 seconds) to reach the Earth, which is 1.5x10^11 meters away from the sun
and the height of the building doesn't matter at all.
joules