Question

find the resistance of an electric lamp if lamp uses 20A when connected to a 220V line

Answer 1

As, V = IR
So, R = V/I
= 220/20 = 11

Answer 2

By using Ohm's law,

                   V= I × R

                   R= V÷ I

                   R= 220/20

                    R= 11 Ω