When a `12 V` battery is connected across an unknown resistor, there is a current of `2.5 mA` in the circuit. Find the value of the resistance of the resistor.

Explanation

Here, `V = 12 V, I = 25 mA = 2.5 xx 10^-3 A`
Resistance of the resistor, `R = (V)/(I) = (12 V)/(2.5 xx 10^-3 A) = 4800 Omega = 4.8 k Omega`.