Question

Which of the following statement(s) are correct regarding heat?

• A. Heat transfer between two bodies through conduction requires direct contact between the two bodies.
• B. Heat transfer through convection is only possible in liquids and gases.
• C. Heat transfer cannot occur in the absence of any physical medium between two objects.
• D. Heat transfer always occur from a body at a higher temperature to a body at lower temperature.

Answer 1

Answer: (A), (B), (D)

The correct options are
A

Heat transfer between two bodies through conduction requires direct contact between the two bodies.

B

Heat transfer through convection is only possible in liquids and gases.

D

Heat transfer always occur from a body at a higher temperature to a body at lower temperature.

Conduction, convection and radiation are the three modes of heat transfer. Conduction can happen in solids whereas convection can only occur in liquids and gases. Heat transfer through radiation can happen in the absence of a physical medium between two bodies. That is how heat from the sun reaches the earth. Heat always flows from higher temperature to lower temperature.