A potentiometer consisting of a wire of length L0 has a source of emf, ɛ connected across it. When a standard cell with emf V = 6V, in series with a voltmeter, is connected at one end of the wire and at a distance L = 4 cm along the wire the voltmeter circuit is in balance and the voltmeter reads zero. When the standard cell is replaced by a source of unknown emf the new balance length is found to be 6 cm. What is the unknown emf? Select one: a. 9 V b. 8 V c. 4 V d. 3 V

A potentiometer consisting of a wire of length L0 has a source of emf, ɛ connected across it. When a standard cell with emf V = 6V, in series with a voltmeter, is connected at one end of the wire and at a distance L = 4 cm along the wire the voltmeter circuit is in balance and the voltmeter reads zero. When the standard cell is replaced by a source of unknown emf the new balance length is found to be 6 cm. What is the unknown emf? Select one: a. 9 V b. 8 V c. 4 V d. 3 V

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter29: Dc Generators

Section: Chapter Questions

Problem 1PA: You are working as an electrician in a large steel manufacturing plant, and you are in the process...

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