Question

Three resistor 2 ohm 3 ohm and 4 ohm are connected to the same battery turn-by-turn in which the power dissipation (rate of heat production)
will be maximum and why

Answer 1

Let emf of the battery is E.

we know, power dissipation is given by, $P=\frac{V^2}{R}$

where V is potential applied across of resistor of resistance R.

for resistor of resistance 2ohm,

Power dissipation, $P_1=\frac{E^2}{2}$

for resistor of resistance 3ohm,

power dissipation, $P_2=\frac{E^2}{3}$

for resistor of resistance 4ohm,

power dissipation, $P_3=\frac{E^2}{4}$

here it is clear that power dissipation by resistor of resistance 2ohm will be maximum.

• reason : it is clear that power dissipation is inversely proportional to resistance when it is applied to the same battery. here minimum value of resistance is 2ohm, so power dissipation by 2ohm will be maximum.