This question was previously asked in

Airforce Group X 4 November 2020 Memory Based Paper

Option 4 : remain same

Group X 2021 Full Mock Test

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70 Questions
70 Marks
60 Mins

The correct option is 4

__CONCEPT__:

Drift velocity: In a material, The average velocity attained by charged particles due to an electric field is called drift velocity.

Drift velocity of the electrons is calculated by:

\(\Rightarrow v_d=\frac{I}{neA}\)

Where I = current in the wire, n = number density of free electrons in the wire, A = cross-sectional area of the wire, and e = charge on one electron

__CALCULATION__:

Drift velocity of electrons in a current-carrying wire of cross-sectional area A and current I is

\(\Rightarrow v=\frac{I}{neA}\)

Drift velocity of the electron, when electric current and the cross-sectional area is doubled is

\(\Rightarrow v'=\frac{I'}{neA'}=\frac{2I}{2neA}=v\)

\([\because v=\frac{I}{neA}]\)

Therefore the new drift velocity will remain the same. Hence option 4 is correct.