Question on electricity. AWESOME

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The discussion centers on a physics problem involving a power supply with an electromotive force (e.m.f) E and internal resistance R, connected to a 10 kΩ resistor. The current drawn is 0.91 A, and a voltmeter with an internal resistance of 10 kΩ reads 8.3 V when connected in parallel. The calculated e.m.f is 10 V and the internal resistance of the power supply is determined to be 1 kΩ, as confirmed by the reference book. The problem emphasizes the importance of measuring current before connecting additional components like the voltmeter.

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henglin
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Physics electricity question!?
A power supply of e.m.f E and internal resistance R is connected to a 10kO(O for ohm) resistor. The current drawn from the power supply is 0.91 A. A voltmeter of internal resistance 10kO is connected in parallel with the 10kO resistor, and read 8.3V. Calculate the e.m.f. and the internal resistance of the power supply.

answer is 10V and 1kO from the book.

thanks.
 
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Welcome to PF!

Hi henglin! Welcome to PF! :smile:

(have an ohm: Ω :wink:)

Are you sure the voltmeter isn't one kΩ ? :confused:
 


tiny-tim said:
Are you sure the voltmeter isn't one kΩ ? :confused:

I'm sure this problem is correct. Note that the 0.91 A is measured before the voltmeter
is connected.
 

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