A potentiometer wire, 10 m long, has a resistance of 40 Ω . It is connected in series with a resistance box and a 2 V storage cell. If the potential gradient along the wire should be 0.1 mV cm - 1 , the resistance unplugged in the box is

Question

A potentiometer wire, 10 m long, has a resistance of 40 Ω . It is connected in series with a resistance box and a 2 V storage cell. If the potential gradient along the wire should be 0.1 mV cm - 1 , the resistance unplugged in the box is, 260 Ω, 760 Ω, 960 Ω, 1060 Ω

MARKS App · Accepted Answer

The potential gradient along the wire = potential difference along wire length of wire or, 0.1 × 10 − 3 = I × 40 1000 V cm - 1 or, Current in wire, I = 1 400 A or, 2 40 + R = 1 400 or R = 800 − 40 = 760 Ω

Search any question & find its solution

Looking for more such questions to practice?