1 Answer
In theory, an ammeter should have zero resistance because we want it to measure current without affecting the circuit. However, in practice, no ammeter has absolutely zero resistance.
Here's why:
Why is it important?
The resistance of the ammeter adds a small voltage drop when inserted into a circuit. If the ammeter's resistance is too high, it could affect the current, which would make the measurement inaccurate. That's why high-quality ammeters are designed with very low resistance.
So, while an ammeter's resistance should be as close to zero as possible, in real life, it can't be truly zero.
Here's why:
- Ideal Ammeter: An ideal ammeter would have no resistance, so it would not affect the flow of current in the circuit. It would simply measure the current without causing any voltage drop or altering the current flow.
- Real Ammeter: Real ammeters, however, always have a small resistance, even if it's very low. This is because of the internal components and wires inside the ammeter. The resistance is usually designed to be so small that it has negligible impact on the circuit, but it's never exactly zero.
Why is it important?
The resistance of the ammeter adds a small voltage drop when inserted into a circuit. If the ammeter's resistance is too high, it could affect the current, which would make the measurement inaccurate. That's why high-quality ammeters are designed with very low resistance.So, while an ammeter's resistance should be as close to zero as possible, in real life, it can't be truly zero.