In europe the standard voltage in homes is 220 v instead of the 120 v used in the united states. therefore a "100-w" european bulb would be intended for use with a 220-v potential difference (see problem 25.40). (a) if you bring a "100-w" european bulb home to the united states, what should be its u. s. power rating? (b) how much current will the 100-w european bulb draw in normal use in the united states?

Avoltage source vs = 10 v is in series with a resistor of 10 kohm. if the source transformation theorem is applied, what will the value of the current source be in ma ?

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

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?