Question

The difference between ammeter and voltmeter is that - 

1. Ammeter has low resistance and voltmeter has higher resistance
2. Ammeter is used to measure current and voltmeter is used to measure voltage
3. Ammeter is connected in series and voltmeter is connected in parallel
4. All of the above

Answer 1

Correct Answer - Option 4 : All of the above

The correct answer is option 4) i.e. All of the above

CONCEPT:

• Ammeter: It is a device used to measure the current in a circuit. It is generally connected in series in a circuit. 
• Voltmeter: It is a device used for measuring the electric potential difference between two points in an electric circuit. It is connected in parallel across the two points to measure the voltage drop between the points.

EXPLANATION:

• An ammeter is used to measure current and a voltmeter is used to measure voltage.
• The ammeter is connected in series as it has to measure the current passing through an appliance that is in series with the ammeter. The voltmeter is connected in parallel as the voltage is always measured between two points.
• In a series connection, the current remains constant.

From Ohms law, V = IR.

• Thus, the greater the resistance of the ammeter, the lesser the current through the ammeter. So, in order to measure the maximum current in the circuit, the ammeter has low resistance.
• A voltmeter is connected in parallel across two points. So, it should have very high resistance such that it doesn't draw any current through it.
• Hence, all the given statements are correct.