Assertion : The drift velocity of electrons in a metallic wire will decrease, if the temperature of the wire is increased.
Reason : On increasing temperature, conductivity of metallic wire decreases.

Options

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

Answer

B

Explanation

(b) On increasing temperature of wire the kinetic energy of free electrons increase and so they collide more rapidly with each other and hence their drift velocity decreases. Also when temperature increases, resistivity increase and resistivity is inversely proportional to conductivity fo material.