Question

An automotive air conditioner produces a 1-kW cooling effect while consuming 0.75 kW of power. What is the rate at which heat is rejected from this air conditioner

Answer 1

The rejected by the air conditioning system is 1.75 kilowatts.

Step-by-step explanation:

A air conditioning system is a refrigeration cycle, whose receives heat from cold reservoir with the help of power input before releasing it to hot reservoir. The First Law of Thermodynamics describes the model:

`\dot Q_(L) + \dot W - \dot Q_(H) = 0`

Where:

`\dot Q_(L)` - Heat rate from cold reservoir, measured in kilowatts.

`\dot Q_(H)` - Heat rate liberated to the hot reservoir, measured in kilowatts.

`\dot W` - Power input, measured in kilowatts.

The heat rejected is now cleared:

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

If
`\dot Q_(L) = 1\,kW` and
`\dot W = 0.75\,kW`, then:

`\dot Q_(H) = 1\,kW + 0.75\,kW`

`\dot Q_(H) = 1.75\,kW`

The rejected by the air conditioning system is 1.75 kilowatts.