If mass a is 1.0 kg, mass b is 5.0 kg, and the frictionless pulley has a mass of 0.5 kg and a radius of 0.15 m, what is the velocity of a and b at 0.5 seconds? a. a = -3.27 m/s, b = 3.27 m/s c. a = 3.27 m/s, b = -3.27 m/s b. a = 1.82 m/s, b = 0.18 m/s d. a = 0.18 m/s, b = 1.82 m/s

Select the correct answer from each drop-down menu. compared to its surroundings, the concentration of solutes is low inside a cell. so, the cell is with respect to its surroundings. a particular solute in this cell uses energy for its transport from the cell to its surroundings. this type of transport is called

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

If we relied solely on the nonrenewable resources found in the u.s., which one would we run out of first at current usage levels? a. natural gas b. oil c. uranium d. coal