00:01
Okay, in this problem we will use the kernel of formula.
00:05
Voltage equals to the total current times the total resistance.
00:11
So we have five different loops.
00:14
And that means we have five different linear equations.
00:19
So for the first loop, we have 9 i1 minus i2 minus i4 minus four times i5 equals to 50.
00:29
The second loop minus i1 plus 7 i2 minus twice of i3 minus 3 i5 equals to 30 so it should be minus 30 so be careful about this on the direction of the battery sign is different with the direction of current that means we have a minus in front of this voltage for the third loop, minus 2 i2 plus 10i3, minus 3i4, minus 3i5 equals to 20.
01:08
The next loop will be minus i1, minus 3i3 plus 7i4, minus 2 times i5 equals to minus 40.
01:20
So there's another negative sign here for the same reason.
01:25
And for the last loop, we don't have any voltage.
01:29
That means the total voltage equals to 0...