4) A battery with unknown emf (e) and internal resistance (r) is connected 7 puan to a circuit that involves an ideal voltmeter, a switch, and two resistors R1 =1 Q, R2 =10 Q, as shown below. When the switch is connected to a, the voltmeter reads 7 V. When the switch is connected to b, the voltmeter reads 10 V. Calculate the value of the internal resistance r.

4) A battery with unknown emf (e) and internal resistance (r) is connected 7 puan to a circuit that involves an ideal voltmeter, a switch, and two resistors R1 =1 Q, R2 =10 Q, as shown below. When the switch is connected to a, the voltmeter reads 7 V. When the switch is connected to b, the voltmeter reads 10 V. Calculate the value of the internal resistance r.

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter29: Direct Current (dc) Circuits

Section: Chapter Questions

Problem 19PQ

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