Question 355: Current Electricity

Question

In the circuit shown, a four-wire potentiometer
is made of a 400 cm long wire, which extends
between A and B. The resistance per unit length
of the potentiometer wire is r = 0.01 $$\Omega $$/cm. If
an ideal voltmeter is connected as shown with
jockey J at 50 cm from end A, the expected
reading of the voltmeter will be :-

Accepted Answer

Resistance of wire AB = 400 ÃÂ 0.01 = 4 $$\Omega $$
i = $${3 \over 6} = 0.5A$$
Now voltmeter reading = i (Resistance of 50 cm
length)
= (0.5 A) (0.01 ÃÂ 50) = 0.25 volt

Answer

0.25 V

Answer

0.20 V

Answer

0.50V

Answer

0.75 V

Current Electricity

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