An electric heater is constructed by applying a potential difference of 110 V across a wire with a resistance of 5.0 Ω. What is the power rating of the heater?
A) 2.0 kW
B) 2.4 kW
C) 1.7 kW
D) 1.5 kW
E) 60 kW

Question

Quizplus · Accepted Answer

The power rating of the heater can be calculated using the formula P = V^2/R where V is the voltage applied and R is the resistance of the wire. 
P = (110 V)^2 / 5.0 Ω = 2420 W = 2.4 kW (rounded to one decimal place)

An Electric Heater Is Constructed by Applying a Potential Difference