Topic: Heat Transfer
Which of the following is FALSE?
- A. Heat flow by conduction is directly proportional to the area and temperature gradient
- B. Heat flow by convection is directly proportional to the area and temperature difference
- C. Heat flow by radiation is directly proportional to the cube of absolute temperature of the radiating body
- D. Emissivity of a perfect black body is unity
Answer: C. Heat flow by radiation is directly proportional to the cube of absolute temperature of the radiating body
Explanation: Heat flow by radiation is directly proportional to the fourth power of the absolute temperature (Stefan-Boltzmann Law), not the cube.