NEETPhysicsCurrent Electricity
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A) : Drift velocity of electron in a metallic wire will decrease if temperature of wire is increased Reason (R) : On increasing temperature conductivity of metallic wire decreases. In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- ABoth (A) and (R) are true and (R) is the correct explanation of (A).
- BBoth (A) and (R) are true and (R) is NOT the correct explanation of (A).
- C(A) is true but (R) is false.
- D(A) is false but (R) is true.
Correct answer
B. Both (A) and (R) are true and (R) is NOT the correct explanation of (A).
Step-by-step solution
Increase in temperature causes atoms to vibrate more, which increases the number of collisions electrons suffer and decrease the drift velocity. OR ( aligned & v _ d = E = ( e ~m ) E & = n e^2 ~m & . v _ d , (temp. ; ) aligned )