Question

A piece of wire or resistance 5 Ohm is drawn out so that it's length is increased to twice it's original length calculate the resistance wire in the new situation.

Answer 1

Given resistance = R1 = 05 ohm

Let length of the wire = L

Therefore, new length of the wire = 2L

Since, when the length is doubled, cross sectional area of the wire becomes half.

Therefore, new resistance = R = 2L/ (A/2) =4L/A

R = 4 x 5 (since, L/A = resistance)

R = 20 ohm.

Answer 2

is Resistance is directly proportional to the length of the wire hence the resistance of the wire of length 5 M equals to 2 into 5 that is equal to new resistance wire equals to 10 Ohm