MEDIUM
12th ICSE
IMPORTANT
Earn 100

The specific resistance of Nichrome is 100 μΩ-cm. What will be the resistance of a Nichrome wire of 5 m length and 0.01 cm2 area of cross-section?

Important Questions on Electric Resistance and Ohm's Law

HARD
12th ICSE
IMPORTANT
A piece of copper of mass 50 g is drawn into a wire of length 50 m. Find the resistance of the wire. The density and the specific resistance of copper are 8.9 × 103 kg m-3  and 1.7 × 10-8 Ω-m respectively.
HARD
12th ICSE
IMPORTANT
A thick wire of 10 Ω resistance is drawn into a thin wire so that its length becomes three times. Calculate its new resistance.
HARD
12th ICSE
IMPORTANT
A wire of resistance 32 Ω is melted and redrawn into wire of half its original length. Find the resistance of the new wire.
HARD
12th ICSE
IMPORTANT
1-kg piece of copper is drawn into a wire 1 mm thick and another piece into a wire 2 mm thick. Compare the resistances of these wires.
HARD
12th ICSE
IMPORTANT

Two copper wires A and B of equal masses are taken. The length of A is double the length of  B. If the resistance of the wire B. If the resistance of wire A is 160Ω, then calculate the resistance of wire B.

HARD
12th ICSE
IMPORTANT
200 V bulb takes a current of 0.2 A. The length of its filament is 22 cm and the specific resistance of the material of the filament is 7 × 10-5 Ω-cm. Find the radius of the filament (π = 227).
HARD
12th ICSE
IMPORTANT

A rectangular block of iron has dimensions 1.2 cm × 1.2 cm ×15 cm. Compute the resistance of the block between the two square ends. The specific resistance of iron at room temperature is 9.68 × 10-8  Ω m.

HARD
12th ICSE
IMPORTANT
A rectangular block of iron has dimensions 1.2 cm × 1.2 cm × 15 cm. Compute the resistance of the block between the two opposite rectangular faces. The specific resistance of iron at room temperature is 9.68 × 10-8 Ω m.