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Assertion : The electric bulbs glows imm...

Assertion : The electric bulbs glows immediately when switch is on.
Reason : The drift velocity of electrons in a metallic wire is vary high.

A

Both A and R are true and R is the correct explanation of A.

B

Both A and R are true but R is NOT the correct explanation of A

C

A is true but R is false.

D

A is false and R is true.

Text Solution

Verified by Experts

The correct Answer is:
A
In a conductor there are large numbers of free electrons. When we close the circuit, the electric field is established instantly with the speed of electromagnetic wave which causes electron drift at every portion of the circuit. Due to which the current is set up in the entire circuit instantly. The current which is set up does not wait for the electrons flow from one end of the conductor to another end. It is due to this, the bulb glows immediately when switch is ON.
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