If a burning log is a black object with a surface area of 0.25 m2 and a temperature of 800 8c, how much power does it emit as thermal radiation?

The correct answer of this question: 18789.79 watt.

EXPLANATION:

As per the question, the surface area of the log is given as A =

The temperature of the of the surface of the log t = 800

We know that

                      ⇒ 800 degree celsius= 800+273 K

                                                           = 1073 K.

Here, K stands for kelvin scale.

We are asked to calculate the thermal power radiation .

The power is defined as the amount of energy released per unit time.

Hence, power is calculated as-

                                Power P =

                                               =

                                               = 18789.79 watt.      [ans]

Here, is the Stefan-Boltzmann constant and T is the absolute temperature of the log.

if i am correct, your answer choices are:

a. the temperature remains constant

b. the temperature increases at a constant rate

c. heat flows at a constant rate into the system

d. heat flows at a constant rate out of the system

e. no heat flows into or out of the system

if so, then the answer is e. no heat flows into or out of the system.