Question

the potential difference required to pass a current 0.2 A in a wire of resistance 10 ohm
a.20v
b.4v
c.2v
d.100v

Answer 1

by ohms law
v=ir
then
v=0.2*10
v=2
hence, the potential difference required is 2volt
(c)2v is the right answer

Answer 2

We know that
$r = \frac{v}{i}$
here
r=resistance
v=potential difference
i=electic current
then,
$r = \frac{v}{i} \\ = > v = r.i \\ = > v = 10 \times \frac{2}{10} \\ = > v = 10 \: volts$