If a burning log is a black object with a surface area of 0.35 m2 and a temperature of 800 ¢ªC, how much power does it emit as thermal radiation?

To calculate the power emitted as thermal radiation by the burning log, we can use Stefan-Boltzmann law. This law states that the power radiated by an object is proportional to its surface area and fourth power of its temperature. The formula is given as:

Power = σ * A * T^4

Where:
Power is the power emitted as thermal radiation
σ (sigma) is the Stefan-Boltzmann constant, approximately equal to 5.67×10^-8 W/m^2K^4
A is the surface area of the object
T is the temperature of the object in Kelvin

Now, let's calculate the power emitted as thermal radiation by the burning log.

Step 1: Convert the temperature from Celsius to Kelvin.
T(K) = T(°C) + 273.15
T(K) = 800°C + 273.15
T(K) = 1073.15 K

Step 2: Plug the values into the formula and calculate the power.
Power = σ * A * T^4
Power = (5.67×10^-8 W/m^2K^4) * 0.35 m^2 * (1073.15 K)^4

After performing the calculations, we can find the power emitted as thermal radiation by the burning log.