A galvanometer acting as a voltmeter will have [2004]a)a low resistance in series with its coil.b)a high resistance in parallel with its coilc)a high resistance in series with its coild)a low resistance in parallel with its coilCorrect answer is option 'C'. Can you explain this answer?

Question

A galvanometer acting as a voltmeter will have      [2004]a)a low resistance in series with its coil.b)a high resistance in parallel with its coilc)a high resistance in series with its coild)a low resistance in parallel with its coilCorrect answer is option 'C'. Can you explain this answer?

Answer

To work as voltmeter, the resistance of galvanometer should be high. A voltmeter indeed is a modified form of a pivoted coil galvanometer. Since, the resistance of coil of galvanometer of its own is low, hence to convert a galvanometer into a voltmeter, its resistance is to be increased. For this an appropriate high resistance is joined in series with the galvanometer .

The value of this resistance to be connected depends on the range of the voltmeter.

NOTE: A voltmeter is always connected in parallel in an electric circuit.

Answer

To convert galvanometer into voltmeter we connect shunt (high resistance wire) in series combination.

Answer

C

Answer

A galvanometer is a device used to detect and measure small electric currents. When used as a voltmeter, a galvanometer is modified by adding a high resistance in series with its coil. This modification allows the galvanometer to measure voltage.

Explanation:
1. Purpose of a voltmeter:
- A voltmeter is used to measure the potential difference (voltage) across a component or circuit.
- It is connected in parallel with the component or circuit under test.
- The voltmeter measures the voltage drop across the component or circuit, providing the user with the numerical value of the potential difference.

2. The working principle of a galvanometer:
- A galvanometer is an instrument that detects and measures electric currents.
- It consists of a coil of wire suspended within a magnetic field.
- When an electric current flows through the coil, it experiences a force due to the interaction between the magnetic field and the current-carrying wire.
- This force causes the coil to rotate, and the deflection of the coil indicates the magnitude and direction of the current.

3. Modifying a galvanometer into a voltmeter:
- To convert a galvanometer into a voltmeter, a high resistance is added in series with the coil.
- This additional resistance is called a multiplier resistor or a shunt resistor.
- The purpose of the multiplier resistor is to limit the current flowing through the galvanometer coil when measuring voltage.
- The resistance of the multiplier resistor is carefully chosen to ensure that the majority of the current passes through the resistor, bypassing the galvanometer coil.
- By doing so, the voltage drop across the resistor is proportional to the voltage being measured.
- The galvanometer coil, being in series with the multiplier resistor, detects this voltage drop and provides a reading on the galvanometer scale.

4. Choice C - High resistance in series with the coil:
- The correct answer is option C, which states that a galvanometer acting as a voltmeter will have a high resistance in series with its coil.
- This is because the series resistance limits the current flowing through the coil, allowing the galvanometer to measure voltage without being damaged by excessive current.
- The high resistance in series ensures that the majority of the current passes through the multiplier resistor, allowing the galvanometer to accurately measure the voltage drop across the resistor and provide a corresponding reading.

Answer

Hiii

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