- Introduction
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- Electric current and Current density
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- Drift Velocity
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- Relation between drift velocity and electric current
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- Ohm's Law and Resistance
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- Resistivity and conductivity
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- variation of resistivity with temperature
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- Current Voltage relations
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- Colour code of carbon resistors
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- Combination of Resistors

A cylindrical tube of length L has inner radius a and outer radius b as shown below in the figure

Given that ρ is the resistivity of the material. Find the resistance of the tube between its ends.

α

If a copper wire is stretched to make it .2% longer. Find the percentage change in the resistance

An electric current of 5 A passes through a circuit containing three wires(A,B,C) of the same material .Length of the wires in the circuit are in the ratio 2:3:4 And their diameters are in the ratio 3:4:5.Find the amount of current flowing in each branch of the circuit when wires are arranged in parallel combination

Find the equivalent resistance between point A and B in following combination of resistors

The current density across a cylindrical conductor of Radius A varies according to the following relation

Where

Find the current through cylindrical cross-section

Class 12 Maths Class 12 Physics