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saw176
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Homework Statement
An ammeter whose internal resistance is 63 ohm reads 5.25 mA when connected in a circuit comtaining a battery and two resistors in series whose values are 750 ohm and 480 ohm. What is the actual current when the ammeter is absent?
Homework Equations
V = IR
Rseries = R1 + R2
The Attempt at a Solution
First I found the voltage using the internal resistance of the ammeter and the current:
V = IR
V = 5.25 x 10-3 (63) = 0.33 V
Then I added the two resistances in series to find the total resistance
R = 750 + 480 = 1230 ohm
Then I tried to apply V = IR with the new resistance to find the current
0.33 V = I (1230 ohm)
And get a value of 2.68 x 10-4A, which is not correct (correct answer: 5.52 x 10-3)
I'm not very good at these problems, so I have a feeling I'm doing something silly wrong, thanks for the input!