Question

A typical electric refrigerator has a power rating of 500 Watts, which is the rate (J/s) at which electrical energy is supplied to do work needed to remove heat from the refrigerator. If the refrigerator releases heat to the room at a rate of 800 Watts, at what rate (in Watts) does it remove heat from inside of the refrigerator?

Answer 1

The rate of heat removed from inside the refrigerator is 300 watts.

Step-by-step explanation:

By the First Law of Thermodynamics and the definition of a Refrigeration Cycle, we have the following formula to determine the rate of heat removed from inside the refrigerator (
`\dot Q_(L)`), in watts:

`\dot Q_(L) = \dot Q_(H)-\dot W` (1)

Where:

`\dot Q_(H)` - Rate of heat released to the room, in watts.

`\dot W` - Rate of electric energy needed by the refrigerator, in watts.

If we know that
`\dot Q_(H) = 800\,W` and
`\dot W = 500\,W`, then the rate of heat removed from inside the refrigerator is:

`\dot Q_(L) = \dot Q_(H)-\dot W`

`\dot Q_(L) = 300\,W`

The rate of heat removed from inside the refrigerator is 300 watts.