Question

Which among the following statement is correct?

• A. All substances expand on heating.
• B. Heat energy flows from hot body to the cold body.
• C. All substances contract on cooling.
• D. Heat energy flows from cold body to the hot body.

Answer 1

The correct option is B Heat energy flows from hot body to the cold body.

Heat energy flows from a hot body to a cold body. In general, all substances expand on heating and contract on cooling but there are some substances, which in some temperature range behave exactly opposite to the normal i.e. they expand on cooling and contract on heating, one such substance is water.