Two baseballs of the same mass were hit by two different players. One baseball travelled faster than the other baseball. Write an explanation for why the baseballs travelled at different speeds. Include
vocabulary terms:force, balanced/unbalanced and exert.

Ten students stand in a circle and are told to make a transverse wave. what best describes the motion of the students? each student bumps the shoulder of his or her neighbor. at the exact time, all students take a step to the right. the students skip clockwise, going in a circular motion. one at a time, each student lifts his or her hands up and then down.

Describe the path of a ray that approaches a mirror parallel to the principal axis.

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt, c and rt, h, and qin, as where rtot rt, c rt, h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc, n 0.05 k/w and rh, n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh, d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th, i tc, i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc