Which of the following statements about thermal radiation is always true?
A) A hot object emits more radiation per unit surface area than a cool object.
B) A cold object produces more total infrared and radio emission per unit surface area than a hot object.
C) A hot object produces more total infrared emission than a cooler object.
D) All the light emitted by hot object has higher energy than the light emitted by a cooler object.
Answer: A