Question

A 120 Ω resistor, a 60 Ω resistor, and a 40 Ω resistor are connected in parallel and placed across a potential difference of 12.0 V. What is the equivalent resistance of the parallel circuit?

Answer 1

The equivalent resistance of the parallel circuit would be 20 Ω

Step-by-step explanation:

To calculate the resistance of resistors connected in parallel, the formula to be used is

1/R = 1/R₁ + R₂ + R₃ + R₄...

1/R = 1/120 + 1/60 + 1/40

1/R = (1 + 2 + 3)/120

1/R = 6/120

1/R = 1/20 Ω

This can be rewritten or cross-multiplied to be

R × 1 = 20 × 1

R = 20 Ω

The equivalent resistance (R) would then be 20 Ω