Two 20-ohm resistors are connected in parallel. What is their equivalent resistance?

NASCLA Electrical exam practice question · Electrical Theory & Principles

Two 20-ohm resistors are connected in parallel. What is their equivalent resistance?

A400 ohms
B20 ohms
10 ohms
D40 ohms

Where to look it up

Explicit exercise assumptions; not a universal code requirement.

Why C is correct

1/R = 1/20 + 1/20, so R = 10 ohms. Equal parallel resistors have half the resistance of one branch; adding to 40 ohms would describe series connection.

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Two 20-ohm resistors are connected in parallel. What is their equivalent resistance?

Two 20-ohm resistors are connected in parallel. What is their equivalent resistance?

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