Assertion : While measuring the thermal conductivity of liquid experimentally, the upper layer is kept hot and the lower layer kept cold.
Reason : This avoids heating of liquid by convection.

Options

A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. If assertion is true but reason is false.
D. If the assertion and reason both are false.

Answer

A

Explanation

We know that to measure thermal conductivity of liquids experimentally, they must be heated from the top i.e., upper layer is kept hot and lower layer is kept cold, so as to prevent convection in liquids.