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Assertion: The drift speed of electrons ...

Assertion: The drift speed of electrons in metals is of the order of few mm / s and charge of an electron is very small `(1.6 xx 10^(-19) C)`. Yet a large amount of current is obtained.
Reason: At room temperature, the thermal speed of electron is very high (`10^7` times the drift speed).
Which one of the following statements is correct?

A

Both assertion and reason are true and reason explains assertion correctly,

B

Both assertion and reason are true and reason does not explains assertion correctly.

C

Assertion is true and reason is false.

D

Assertion is false and reason is true.

Text Solution

Verified by Experts

The correct Answer is:
B
Current depends on (0) Charge (ii) dri speed (iii) area and (iv) no. of free clectrons p unit volume of a metal.
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