Sam records the temperatures of two cups of ice. Which best explains why the temperatures stop changing after several hours? A. One cup has given all of its heat energy to the other cup.
B. Each cup reaches the same temperature as the other cup.
C. The two cups reach the same temperature as the surrounding air.
D. All of the ice melts in the two cups, so their temperatures stop changing.

Energy is the ability to do work which measures what

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.

An astronaut in space cannot use a scale or balance to weigh objects because there is no gravity. but she does have devices to measure distance and time accurately. she knows her own mass is 77.4 kg , but she is unsure of the mass of a large gas canister in the airless rocket. when this canister is approaching her at 3.50 m/s , she pushes against it, which slows it down to 1.30 m/s (but does not reverse it) and gives her a speed of 2.60 m/s . what is the mass of the canister?