Heat I. is a form of energy II. is measured with a thermometer III. cannot be created or destroyed IV. from a…

Analyze the question: We must decide which of the four statements about heat are true.

Check each statement:

• I. Heat is a form of energy. TRUE. Heat is thermal energy in transit, measured in joules.
• II. Heat is measured with a thermometer. FALSE. A thermometer measures temperature, not heat. Heat is measured with a calorimeter (in joules or calories). This is a classic confusion between heat and temperature.
• III. Heat cannot be created or destroyed. TRUE in the sense of the law of conservation of energy: energy can only be converted from one form to another. (Heat can be produced by converting other energy forms, such as friction turning mechanical energy into heat, but this is conversion, and the standard textbook reading here is that energy is conserved.)
• IV. Heat from a hot object is transferred through conduction only. FALSE. Heat is transferred by conduction, convection and radiation.

Correct statements: I and III only.

Tip: Remember "Heat = energy (joules), Temperature = hotness (thermometer)". Also, whenever you see the word "only" in a statement about heat transfer, be suspicious, because there are three modes: conduction, convection and radiation.