Question

Calculate the rate of heat transfer by radiation from a car radiator at 110°C into a 50.0ºC environment, given an emissivity of 0.750 and a 1.20-m² surface area.

a) 722 W
b) 855 W
c) 987 W
d) 1,112 W

Answer 1

The rate of heat transfer by radiation from the car radiator to the environment is approximately 987 W. Therefore, the correct option is c.

Step-by-step explanation:

The rate of heat transfer by radiation can be calculated using the Stefan-Boltzmann Law, which states that the power radiated per unit area is proportional to the fourth power of the absolute temperature and is given by the equation:

`\[ P = \varepsilon \sigma A (T_1^4 - T_2^4) \]`

Substituting the given values into the formula:

`\[ P = 0.750 * 5.67 * 10^(-8) * 1.20 \, \text{m}^2 * (383 \, \text{K}^4 - 323 \, \text{K}^4) \]`

`\[ P \approx 987 \, \text{W} \]`

Therefore, the rate of heat transfer by radiation from the car radiator is approximately 987 W, corresponding to option (c).

Therefore, the correct option is c.