A box has two forces acting on it. One force is 100 N upward. Another force is 50 N downward. What is the net force on the box? Choose the correct answer.

50 N upward
50 N upward

100 N upward
100 N upward

50 N downward
50 N downward

100 N downward
100 N downward

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

Which of the following are appropriate acceleration units?

Ajet plane flying 600 m/s experience an acceleration of 4.0 g when pulling out of a circular dive. what is the radius of curvature part of the path in which the plane is flying? a) 7100 m b) 650 m c) 9200 m d) 1200 m