Current Electri...

The resistance of wire is 5 ohm at 50C and 6 ohm at 100C. The resistance of the wire at 0C willbe

A metallic resistor is connected across a battery. If the number of collisions of the free electrons
with the lattice is somehow decreased in the resistor (for example by cooling it), the current
will:

The length of a wire of a potentiometer is 100 cm, and the e.m.f. of its stand and cell is $$\mathrm{E}$$ volt. lt is employed to measure the e.m.f. of a battery whose internal resistance is 0.5 $$\Omega$$. lf the balance point is obtained at $$l=30$$ cm from the positive end, the e.m.f. of the battery is

The Kirchhoffs first law $$(\sum i=0)$$ and second law $$(\sum \sum iR=\sum E)$$ where the symbols have their usual meanings, are respectively based on  

A piece of copper and another of germanium are cooled from room temperature to 77 K, the resistance of : 

A potentiometer circuit is set up as shown. The potential gradient across the potentiometer wire is k volt/cm and the ammeter, present in the circuit, reads 1.0 A when two way key is switched off. The balance points, when the key between the terminals (i) 1 and 2 (ii) 1 and 3, is plugged in, are found to be at lengths $$l_{1}$$cm and $$l_{2}$$ cm respectively. The magnitudes, of the resistors R and X, in ohms, are then, equal respectively to:

The following diagram represents an electrical circuit containing two uniform resistance wires A and B connected to a single ideal cell. Both wires have same length, but thickness of wire B is twice that of wire A. The conducting wires connecting A and B to the ideal cell are resistance less. The dependence of electric potential on position along the length of two wires is given in option.

You have a large supply of light bulbs and a battery. You start with one light bulb connected to the battery and notice its brightness. You then add one light bulb at a time, each new bulb being added in series to the previous bulbs then

Analyse the given statements and choose the

correct option.


Statement 1 : Bending a wire does not affect the electrical

resistance.


Statement 2 : Resistance of a wire is proportional to resistivity

of the material.

In the electric circuit shown in the figure, the effective resistance of two 8 $$\Omega$$ resistors in the combination is :