An ammeter is always connected is series in a circuit because........

Options

A. `20hat(i) + 20hat(j) + 70hat(k)`
B. `10hat(i) + 20hat(j) + 8hat(k)`
C. `30hat(i) + 10hat(j) + 7hat(k)`
D. `15hat(i) + 5hat(j) + 60hat(k)`

Explanation

**Step-by-Step Solution:**

1. **Understanding the Function of an Ammeter:**
- An ammeter is a device used to measure electric current in a circuit. The unit of electric current is the ampere, which is why the device is named "ammeter" (ampere meter).

2. **Connection in Series:**
- An ammeter must be connected in series with the circuit. This is because, in a series circuit, the same current flows through all components. Therefore, the ammeter will measure the total current flowing through the circuit.

3. **Low Resistance of Ammeter:**
- An ammeter is designed to have very low resistance. This is crucial because if the ammeter had high resistance, it would significantly reduce the current flowing through the circuit, leading to inaccurate measurements.

4. **Avoiding Short Circuit:**
- If an ammeter were connected in parallel with a circuit component, it would create a short-circuit path. Since the ammeter has low resistance, most of the current would flow through it instead of the intended path, potentially damaging the ammeter and the circuit.

5. **Power Loss Consideration:**
- The low resistance of the ammeter also ensures that the power loss across the ammeter is minimal. This is important for maintaining the efficiency of the circuit and ensuring accurate current measurements.

6. **Conclusion:**
- Therefore, an ammeter is always connected in series in a circuit to accurately measure the current without affecting the circuit's operation.

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