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 ohm
2.	Less than 10 ohm
3.	More than 10 ohm
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$\mu A/\text{div.}$ 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) $V^{\text{'}}=2V$

(2) $V^{\text{'}}>2V$

(3) $V^{\text{'}}>>2V$

(4) $V\text{'}<2V$

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

A galvanometer with a resistance of 36 Ω is changed into an ammeter by using a shunt of 4 Ω. The fraction f0 of total current passing through the galvanometer will be:

1. $\frac{1}{40}$

2. $\frac{1}{4}$

3. $\frac{1}{140}$ 

4. $\frac{1}{10}$

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

The current flowing in a coil of resistance 90 Ω is to be reduced by 90%. What value of resistance should be connected in parallel with it 

(1) 9 Ω

(2) 90 Ω

(3) 1000 Ω

(4) 10 Ω

A galvanometer of \(50~\Omega \) resistance has 25 divisions. A current of 4 × 10^–4 A gives a deflection of one division. To convert this galvanometer into a voltmeter having a range of 25 V, it should be connected with a resistance of:

1. 2500 Ω as a shunt

2. 2450 Ω as a shunt

3. 2550 Ω in series

4. 2450 Ω in series