Advanced Qualification · A-003 Measurements · A-003-006-001
A meter has a full-scale deflection of 40 microamperes and an internal resistance of 96 ohms. You want it to read 0 to 1 mA. The value of the shunt to be used is:
- A24 ohms
- B16 ohms
- C40 ohms
- D4 ohms
Correct answer: D — 4 ohms. From the official ISED question bank, verified word for word.
Why
To make the meter read up to 1 mA, most of that current must bypass the delicate coil through a parallel resistor called a shunt. The full explanation — and one for every question — is in Pro.
Practise this section
Measurements is section A-003 of the Advanced exam: Measurements: meters, oscilloscopes, counters, signal generators, and what a reading actually tells you.
Drill A-003 — free, no account