(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A dc machine(6W, 120V,1500rpm) is separately excited and delivers rated current at rated terminal voltage.Field winding is connected to 120V supply. R_{fw}=100[tex]\Omega[/tex].

a) Determine the value of field current

b) Determine the value of R_{fc}required.

2. Relevant equations

V_{f}= I_{f}R_{f}

3. The attempt at a solution

In the question the value of V_{f}is given, while both I_{f}and R_{f}are variables. So I need another relation to find out both the values. Is there another relation that I'm missing?

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# Homework Help: DC Machines

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