Question

if the length of a resistor is changed from 10cm to 40cm,What happens to the resistance?Old length=10cm,Old resistance=6ohm?

Answer 1

Answer:

their resistance also changed 6ohm to 24ohm

Answer 2

Resistance = ρl/A

Where, ρ = resistivity of wire

l = Length of wite

A = Area of cross section of wire

So, If we change Length by 4 times then Length will be 4 times and resistivity and Area of cross section will not be affected.

So, New resistance = ρ(4l)/A

New resistance = 4 × ( ρl/A)

New resistance = 4 × Resitance

New resistance = 4 × 6

New resistance = 24 ohm

Therefore, Resitance will be 24 ohm when Length is changed to 40cm.

Hope it helps.......✌