A galvanometer has a coil resistance of 100 Ω and gives a full-scale deflection for 30 mA of current. If it is to work as a voltmeter in the 30 V range, how much resistance does it require to be added?
1. 900
2. 1800
3. 500
4. 1000
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.
2.
3.
4.
The galvanometer of resistance 80 Ω deflects a full scale for a potential of 20 mV. How much resistance is required for a voltmeter to deflect a full scale of 5 V to be made using this galvanometer?
1. | resistance of \(19.92~ \mathrm{k} \Omega\) parallel to the galvanometer |
2. | resistance of \(19.92~ \mathrm{k} \Omega\) in series with the galvanometer |
3. | resistance of \(20 ~\Omega\) parallel to the galvanometer |
4. | resistance of \(20~ \Omega\) in series with the galvanometer |
A galvanometer having a coil resistance of \(60~\Omega\) shows full-scale deflection when a current of 1.0 A passes through it. How can we convert it into an ammeter capable of reading currents up to 5.0 A?
1. | putting in series resistance of \(240 ~\Omega \text {. }\) |
2. | putting in parallel resistance of \(240 ~\Omega \text {. }\) |
3. | putting in series resistance of \(15~ \Omega \text {. }\) |
4. | putting in parallel resistance of \(15~ \Omega \text {. }\) |
A milliammeter of 10 mA has a coil resistance of 1 Ω. To use it as an ammeter of range 1 A, the required shunt must have a resistance of:
1. \(\frac{1}{101}~\Omega \)
2. \(\frac{1}{100}~\Omega \)
3. \(\frac{1}{99}~\Omega \)
4. \(\frac{1}{9}~\Omega \)
A galvanometer of resistance 240 Ω allows only 4% of the main current after connecting a shunt resistance. What is the value of shunt resistance?
1. 10
2. 20
3. 8
4. 5
What properties will a galvanometer that is acting as a voltmeter have?
1. | high resistance in series with its coil | 2. | low resistance in parallel with its coil |
3. | low resistance in series with its coil | 4. | high resistance in parallel with its coil |
On connecting a shunt of \(10 ~ \Omega,\) the deflection in a moving coil galvanometer falls from 40 divisions to 6 divisions. What is the resistance of the galvanometer?
1. | \(\frac{120}{3}~\Omega \) | 2. | \(\frac{30}{7}~\Omega \) |
3. | \(\frac{170}{3}~\Omega \) | 4. | \(\frac{150}{7}~\Omega \) |
When a 12 Ω resistor is connected in parallel with a moving coil galvanometer, its deflection reduces from 50 divisions to 10 divisions. What will be the resistance of the galvanometer?
1. 24 Ω
2. 36 Ω
3. 48 Ω
4. 60 Ω
1. 0.25 amp
2. 0.8 amp
3. 0.2 amp
4. 0.5 amp