An air source heat pump transfers energy from the air outside a building to increase the temperature of the air inside the building - AQA - GCSE Physics Combined Science - Question 6 - 2021 - Paper 1

The energy needed to change the state of the liquid coolant is called the latent heat of vaporization.

Stays the same.

The pressure in the pipe increases because the compressor compresses the coolant vapor, which increases its density. Higher density results in more collisions of the vapor molecules within a confined space, leading to an increase in pressure according to the ideal gas law.

To calculate the specific heat capacity (c) of the air, we can use the formula:

$c = \frac{Q}{m \Delta T}$

Where:

• Q = useful output energy transfer = 1560 kJ = 1,560,000 J
• m = mass of air = 125 kg
• \Delta T = change in temperature = (22.1 °C - 11.6 °C) = 10.5 °C

Substituting the values:

$c = \frac{1,560,000}{125 \times 10.5}$

Calculating gives:

$c = \frac{1,560,000}{1312.5} = 1,187.5 J/kg °C$

In standard form, this is approximately:

$c = 1.19 \times 10^3 J/kg °C$

The advertisement is not correct because it ignores the energy input from the surrounding air. The total energy input to the system must include both the energy from the electricity supply and the energy transferred from the air outside. Furthermore, the efficiency cannot exceed 100% as dictated by the laws of thermodynamics.