PHYS 122 Chapter 29: chapter 29

A certain refrigerator is rated as being 34% as efficient as a Carnot refrigerator. To remove 109 J of heat from the interior at 0 °C and eject it to the outside at 23 °C, how much work must the refrigerator motor do?

Planet Z-34 has a mass equal to one-third that of the earth and aradius equal to 0ne-third that of the earth. with g representingthe acceleration due to gravity on the surface of the earth, theacceleration due to gravity on the surface of Z-34 is
A)g/3 B)g/9 C) 3g D) 9g E) 6g???

A baking dish is removed from a hot oven and placed on a cooling rack. As the dish cools down to 34° C from 168° C, its net radiant power decreases to 12.1 W. What was the net radiant power of the baking dish when it was first removed from the oven? Assume that the temperature in the kitchen remains at 23° C as the dish cools down.