How to Calculate Shunt Resistance for Converting a Galvanometer to an Ammeter?

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SUMMARY

The discussion focuses on calculating the shunt resistance required to convert a galvanometer with a full-scale current of 0.100 mA and a coil resistance of 50 ohms into an ammeter with a full-scale current of 60 mA. The relevant formula for this calculation is s = (Ig / (I - Ig)) * R, where s is the shunt resistance, Ig is the galvanometer's full-scale deflection current, I is the desired current range, and R is the galvanometer's resistance. Substituting the values into the equation yields a required shunt resistance of 0.083 ohms.

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dgresch
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A galvanometer has a full scale current of 0.100 mA and a coil resistance of 50ohmes. In constructing an ammeter of 60mA full scale, what shunt resistnace is needed?I'm lost on this one.
 
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dgresch said:
A galvanometer has a full scale current of 0.100 mA and a coil resistance of 50ohmes. In constructing an ammeter of 60mA full scale, what shunt resistnace is needed?


I'm lost on this one.

You want 0.1mA to go through the 50 Ohm coil, and the rest of the 60mA to go through the low-resistance shunt in parallel with the coil. What do you think the Relevant Equations are?
 
Thanks gneill, I'm new to this and I thought to just post my own thread since I didn't see it on google :P.
 
is the answer 0.083ohm
 
rohans said:
is the answer 0.083ohm

It might be :smile: Can you show your work?
 
s=(Ig/(I-Ig))*R
s-required shunt
R-resistance of galvanometer(50)
Ig-full scale deflection current of the galvanometer(0.1)
I-desired current range(60)
just substitute the given data
 

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