### Two metal wires of identical dimensions are connected in series. If σ₁ and σ₂ are

Two metal wires of identical dimensions are connected in series. If σ₁ and σ₂ are the conductivities of the metal wires respectively, the effective conductivity of the combination is Options (a) σ₁+ σ₂/σ₁ σ₂ (b) […]

### A potentiometer wire of length L and a resistance r are connected in series with

A potentiometer wire of length L and a resistance r are connected in series with a battery of e.m.f. E₀ and a resistance r₁. An unknown e.m.f. E is balanced at a length l of […]

### A circuit contains an ammeter, a battery of 30 V and a resistance 40.8 ohm

A circuit contains an ammeter, a battery of 30 V and a resistance 40.8 ohm all connected in series. If the ammeter has a coil of resistance 480 ohm and a shunt of 20 ohm, […]

### Across a metallic conductor of non-uniform cross-section, a constant potential

Across a metallic conductor of non-uniform cross-section, a constant potential difference is applied. The quantity whilch remain (s) constant along the conductor is Options (a) current density (b) current (c) drift velocity (d) electric field […]

### A,B and C are voltmeters of resistance R, 1.5 R and 3R respectively, as shown

A,B and C are voltmeters of resistance R, 1.5 R and 3R respectively, as shown in the figure. When some potential difference is applied between X and Y, then the voltmeter readings are VA,VB and […]

### A potentiometer wire has length 4m resistance 8Ω. The resistance that must be connected

A potentiometer wire has length 4m resistance 8Ω. The resistance that must be connected in series with the wire and an accumulator of emf 2V, so as to get a potential gradientof 1mV per cm […]

### Two cities are 150 km apart. Electric power is sent from one city to another city

Two cities are 150 km apart. Electric power is sent from one city to another city through copper wires. The fall of potential per km is 8 volt and the average resistance per km is […]

### The resistance in the two arms of the meter bridge are 5Ω and RΩ, respectively

The resistance in the two arms of the meter bridge are 5Ω and RΩ, respectively. When the resistance R is shunted with an equal resistance, then the new balance point is at 1.6l₁. The resistance […]

### In an ammeter, 0.2% of main current passes through the galvanometer

In an ammeter, 0.2% of main current passes through the galvanometer. If resistance of galvanometer is G, then the resistance of ammeter will be Options (a) 1/499 G (b) 499/500 G (c) 1/500 G (d) […]

### A potentiometer circuit has been set up for finding the internal resistance of a given

A potentiometer circuit has been set up for finding the internal resistance of a given cell. The main battery, used across the potentiometer wire, has an emf of 2.0V and a negligible internal resistance. The […]

1 2 3 14