When a potential difference is applied across a cylindrical wire, average drift speed of free electrons is ‘V’. Now the wire is stretched to two times its original length and same potential difference is applied across it. Then the new drift speed of free electrons will be $$______$$

Question

Infinity Learn · Accepted Answer

Volume of wire remains constant.∴ a'l' $$=$$ al ⇒ a' $$=$$ $$al2l$$ $$=$$ $$a2R$$ $$=$$ Initial  resistance  $$=$$ ρla∴ R' $$=$$ ρ.l'a'  $$=$$ ρ$$.2la2$$ $$=$$ $$4RNow$$  Vd $$=$$ iane $$=$$ ERane∴ vd'vd $$=$$ RR'.aa' $$=$$ $$14.2$$  $$=$$ $$12$$∴  v'd $$=$$ $$12vd$$ $$=$$ $$v2$$

Drift velocity

Remember concepts with our Masterclasses.

When a potential difference is applied across a cylindrical wire, average drift speed of free electrons is ‘V’. Now the wire is stretched to two times its original length and same potential difference is applied across it. Then the new drift speed of free electrons will be ______

Ready to Test Your Skills?

free study material

Drift velocity

Remember concepts with our Masterclasses.

When a potential difference is applied across a cylindrical wire, average drift speed of free electrons is ‘V’. Now the wire is stretched to two times its original length and same potential difference is applied across it. Then the new drift speed of free electrons will be ______

Volume of wire remains constant.∴ a'l' = al ⇒ a' = al2l = a2R = Initial resistance = ρla∴ R' = ρ.l'a' = ρ.2la2 = 4RNow Vd = iane = ERane∴ vd'vd = RR'.aa' = 14.2 = 12∴ v'd = 12vd = v2

Ready to Test Your Skills?

free study material