In the circuit shown, a meter bridge is in its balanced state. The meter bridge wire has a resistance 0.1 ohm/cm. The value of unknown resistance X and the current drawn from the battery of negligible resistance is
(1) 6 Ω, 5 amp
(2) 10 Ω, 0.1 amp
(3) 4 Ω, 1.0 amp
(4) 12 Ω, 0.5 amp
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)
The measurement of the voltmeter in the following circuit is :
(1) 2.4 V
(2) 3.4 V
(3) 4.0 V
(4) 6.0 V
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
The potential difference across the 100Ω resistance in the following circuit is measured by a voltmeter of 900 Ω resistance. The percentage error made in reading the potential difference is :
(1)
(2) 0.1
(3) 1.0
(4) 10.0
1. | \(\dfrac{1}{40}\) | 2. | \(\dfrac{1}{4}\) |
3. | \(\dfrac{1}{140}\) | 4. | \(\dfrac{1}{10}\) |
If the ammeter in the given circuit reads 2 A, the resistance R is :
(1) 1 ohm
(2) 2 ohm
(3) 3 ohm
(4) 4 ohm
Two resistances of 400 Ω and 800 Ω are connected in series with a 6-volt battery of negligible internal resistance. A voltmeter of resistance 10,000 Ω is used to measure the potential difference across 400 Ω. The error in the measurement of potential difference in volts approximately is :
(1) 0.01
(2) 0.02
(3) 0.03
(4) 0.05
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