Question

Why Kelvin bridge is used for measurement of low resistance?

(a) due to e.m.f source used

(b) due to a large current flow

(c) due to contact and lead resistance

(d) due to power dissipation across the circuit

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This is a very interesting question from Kelvin Bridge topic in section Measurement of Resistance of Electrical Measurements

Answer 1

Correct answer is (c) due to contact and lead resistance

Explanation: While measuring very low resistances the contact and lead resistances cause significant errors in the value of the measured resistance. As a result Kelvin bridge is used for measurement of low resistances.