Current Electri...

A cell of internal resistance 3 ohm and e.m.f 10 volt is connected to a uniform wire of length 500 cm and resistance 3 ohm. The potential gradient in the wire is

A potentiometer consists of a wire of length 4 m and resistance 10 Ω. It is connected to cell of e.m.f 2 V. The potential difference per unit length of the wire will be

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

A resistance of 2 Ω is connected across one gap of a meter-bridge (the length of the wire is 100 cm) and an unknown resistance, greater than 2 Ω is connected across the other gap. When these resistances are interchanged, the balance point shifts by 20 cm. neglecting any corrections, the unknown resistance is

A 50 ohm galvanometer gets full scale deflection when a current of 0.01 A passes through the coil. When it is converted to a 10 A ammeter, the shunt resistance is

Resistance in the two gaps of a meter bridge are 10 ohm and 30 ohm respectively. If the resistances are interchanged the balance point shifts by

A potentiometer has uniform potential gradient. The specific resistance of the material of the potentiometer wire is 10^–7m² ohm-meter and the current passing through it is 0.1 ampere: cross-section of the wire is 10^–6 m². The potential gradient along the potentiometer wire is

Two resistances of 400 Ω and 800 Ω are connected in series with 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 volt approximately is

An ammeter reads upto 1 ampere. Its internal resistance is 0.81 ohm. To increase the range to 10 A the value of the required shunt is

The length of a wire of a potentiometer is 100 cm, and the e.m.f of its standard cell is E volt. It is employed to measure the e.m.f of a battery whose internal resistance is 0.5 Ω. If the balance point is obtained at l= 30 cm from the positive end, the e.m.f. of the battery is