Question

A current of 200 m/a flows through a 4ohm resistor What is p. d across resistor

Answer 1

As we know the potential difference across a conductor is a multiple of its current flowing through it and Resistance of the conducter:
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so,
V= iR

here
i= 200

R= 4 ohm

so,

V= 200× 4 v

V= 800 v

so the potential difference across a resistor is 800 volt