Resistance and Power - Technical MCQs

Q1:

With 1 mA of current, what wattage rating should a 470 ohm resistor have?

A 1/4 watt

B 1/2 watt

C 1 watt

D 2 watts

ANS:A - 1/4 watt

1/4 watts, 1/2 watts or 1 watts means the physical size of the resistor and not the technical measures.

1/4 watts means the resistor physical size is smaller. This usually uses in experiments or another device that handle a small amount of power.

And 1 watt means the physical size of the resistor is bigger and usually use in high power use to be not destroyed immediately by the current flowing.