Question

If current in a 500 watt heating element is 4 A, what is its resistance?Group of answer choices85.7 Ω42.8 Ω31.3 Ω11.2 Ω

Answer 1

31.3 Ω

Step-by-step explanation

Given:

• The power, P = 500 W

,

• The current, I = 4 A

Unknown:

• The resistance, R

The power of a device with a current I and resistance R is,

`P=I^2\cdot R`

Solving for R,

`R=(P)/(I^2)`

Replace with the known values and solve,

`R=(500W)/(4^2A^2)=31.25\Omega\approx31.3\Omega`

Hence, the resistance of the heating element is 31.3 Ω.