00:01
Here we have a circuit consisting of two parallel branches with the potential difference v, which is equal to 120 volts.
00:10
And this is applied across each of the branch.
00:14
And one branch is the rotor represented by rf, the resistance, and an induced emf that opposes the applied potential.
00:28
And so we, for part, a.
00:33
The field coils and the rotor are in parallel to the applied potential difference.
00:42
So the potential difference from over here, let's call it a and this point will be b.
00:49
So the potential difference across a b is going to be i times r and that is equal to if times rf.
01:01
And from here we can find the current which is equal to v over rf and we get this value to be 1 .13 ampere.
01:18
For part b we apply the junction rule to point a in here and it gives i minus if minus ir equals to 0.
01:34
So this current i over here is basically splitting into two branches, two components, we can say.
01:47
So that's ir and if.
01:50
And from here we can find ir which is equal to i minus if.
01:59
And we know the value of the total current.
02:03
And we found if over here in part a...