Question

A current of 0.2 A flows through a wire whose ends are at a potential difference of 15 V. The resistance of the wire is :

• A. $3\Omega$
• B. $75\Omega$
• C. $5\Omega$
• D. $1.5\Omega$

Answer 1

The correct option is B $75\Omega$

Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. Introducing the constant of proportionality, the resistance, we arrive at the usual mathematical equation that describes this relationship: $I=\frac{V}{R}$,
where, I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms.
Therefore, R=V/I.
$R=\frac{15}{0.2}=75\Omega$