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ehabmozart
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Question about potential difference??
A very long wire carries a uniform linear charge density λ
Using a voltmeter to measure potential difference, you find that
when one probe of the meter is placed 2.5 cm from the wire and
the other probe is 1cm farther from the wire, the meter reads 575 V
(a) What is λ?
Va-Vb= λ/2∏ε0 * ln(rb/ra)
My first question is what does the voltmeter read? Va-Vb or Vb-Va? ... In this case I assume it is Vb-Va.. So in our attempt it should be -575= λ/2∏ε0 * ln(3.5/2.5) .. But this doesn't yield to the answer... Any thoughts!?
Homework Statement
A very long wire carries a uniform linear charge density λ
Using a voltmeter to measure potential difference, you find that
when one probe of the meter is placed 2.5 cm from the wire and
the other probe is 1cm farther from the wire, the meter reads 575 V
(a) What is λ?
Homework Equations
Va-Vb= λ/2∏ε0 * ln(rb/ra)
The Attempt at a Solution
My first question is what does the voltmeter read? Va-Vb or Vb-Va? ... In this case I assume it is Vb-Va.. So in our attempt it should be -575= λ/2∏ε0 * ln(3.5/2.5) .. But this doesn't yield to the answer... Any thoughts!?