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Homework Statement
[/B]An ammeter has a range of 10mA or 0.01A and a resistor of 20Ω.
Three shunts are used:
R1 = 4Ω ; R2 = 2Ω ; R3 = 4Ω
What will the different ranges be (m3, m2, m1)?
The Attempt at a Solution
[/B]I started by calculating the voltage:
Ua = Ia ⋅ Ra
Ua = 0.01A ⋅ 20Ω = 0.2V
Then I started calculating the current for each resistor
I1 = Ia ⋅ Ra / R1 = 0.01A ⋅ 20Ω / 4Ω = 0.05A
I2 = Ia ⋅ Ra / R2 = 0.01A ⋅ 20Ω / 2Ω = 0.1A
I3 = Ia ⋅ Ra / R3 = 0.01A ⋅ 20Ω / 4Ω = 0.05A
And here is where I get lost.
On my answer sheet it says that:
m3 = 0.075A ; m2 = 0.05A ; m1 = 0.03A
Can someone explain me what I'm missing here?
Thanks for reading up until here.
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