Question

A potential difference of 20 volts is applied across the ends of a resistance of 5 ohms. What current will flow in the resistance?

Answer 1

Given,
Potential Difference= V = 20 V
Resistance = I = 5 Ω
By Ohm's law V=IR
Put values:
20 = 5I
Then I = 20/5 = 4 A                    

Answer 2

potential difference[∆v] = 20 volt

resistance[R]= 5 ohm

FROM OHM'S LAW...

V = I×R

I = V/R = 20/5 = 4 amp.(A)