A galvanometer having a resistance of \(8~\Omega\) is shunted by a wire of resistance \(2~\Omega\). If the total current is \(1~\text{A}\), the part of it passing through the shunt will be:
1. \(0.25~\text{A}\)
2. \(0.8~\text{A}\)
3. \(0.2~\text{A}\)
4. \(0.5~\text{A}\)
A voltmeter of resistance 1000 Ω gives full-scale deflection when a current of 100 mA flow through it. The shunt resistance required across it to enable it to be used as an ammeter reading 1 A at full-scale deflection is :
1. 10000 Ω
2. 9000 Ω
3. 222 Ω
4. 111 Ω
If an ammeter \(A\) reads \(2\) A and the voltmeter \(V\) reads \(20\) V, what is the value of resistance \(R\)? (Assuming finite resistances of ammeter and voltmeter)
1. | Exactly \(10~\Omega\) |
2. | Less than \(10~\Omega\) |
3. | More than \(10~\Omega\) |
4. | We cannot definitely say |
A galvanometer has a resistance of 25 ohm and a maximum of 0.01 A current can be passed through it. In order to change it into an ammeter of range 10 A, the shunt resistance required is
1. 5/999 ohm
2. 10/999 ohm
3. 20/999 ohm
4. 25/999 ohm
A galvanometer has 30 divisions and a sensitivity 16 It can be converted into a voltmeter to read 3 V by connecting (approximately):
1. Resistance nearly 6 k Ω in series
2. 6 k Ω in parallel
3. 500 Ω in series
4. It cannot be converted
A voltmeter has a range 0-V with a series resistance R. With a series resistance 2R, the range is 0-V'. The correct relation between V and V' is :
1.
2.
3.
4.
If an ammeter is to be used in place of a voltmeter then we must connect with the ammeter a :
1. Low resistance in parallel
2. High resistance in parallel
3. High resistance in series
4. Low resistance in series
1. | \(\dfrac{1}{40}\) | 2. | \(\dfrac{1}{4}\) |
3. | \(\dfrac{1}{140}\) | 4. | \(\dfrac{1}{10}\) |
A galvanometer, having a resistance of 50 Ω gives a full scale deflection for a current of 0.05 A. The length in meter of a resistance wire of area of cross-section 2.97× 10–2 cm2 that can be used to convert the galvanometer into an ammeter which can read a maximum of 5 A current is (Specific resistance of the wire = 5 × 10–7 Ωm)
1. 9
2. 6
3. 3
4. 1.5
An ammeter reads up to 1 ampere. Its internal resistance is 0.81 ohm. To increase the range to 10 A the value of the required shunt is :
1. 0.09 Ω
2. 0.03 Ω
3. 0.3 Ω
4. 0.9 Ω