Resistivity & Conductivity: JEE Questions & Solutions

Which of the following resistivity () vs temperature (T) curves is most suitable to be used in wire-bound standard resistors?

A wire of length 25 m and cross-sectional area 5 mm^2 having resistivity 2 10^-6 m is bent into a complete circle. The resistance between…

An electric toaster has resistance of 60 at room temperature (27^ C). The toaster is connected to a 220 V supply. If the current flowing…

At room temperature (27^ C), the resistance of a heating element is 50. If the temperature coefficient of the material is 2.4 10^-4 ^ C^-1,…

A hollow cylindrical conductor has a length of 3.14 m, while its inner and outer diameters are 4 mm and 8 mm, respectively. The resistance…

If a copper wire is stretched to increase its length by 20. The percentage increase in resistance of the wire is:

A uniform metallic wire carries a current 2 A. When a 3.4 V battery is connected across it, the mass of the wire is 8.92 10^-3 kg, density…

The resistance of a wire is 5. If it's stretched to 5 times of its original length, its new resistance will be:

A rectangular parallelepiped is measured as 1 cm 1 cm 100 cm. If its specific resistance is 3 10^-7 -cm, then the resistance between its…

A wire of resistance 160 is melted and drawn into a wire of one-fourth of its length. The new resistance of the wire will be:

The current flowing through a conductor connected across a source is 2 A and 1.2 A at 0^ C and 100^ C respectively. The current flowing…