0
\$\begingroup\$

I am a beginner in the electronics so please bear with me for this question. You can see two Voltage sources (V1 and V2) and one Current source (I3). enter image description here

When we start solving the circut, we replace the Current source (I3) with the Voltage source (V3) and we draw three currents going clockwise. But, shouldn't the last current (Iiii) go counterclockwise? Thank you!

\$\endgroup\$
  • \$\begingroup\$ Besides that we do not do homework here, we also have no idea what the questions ask about. \$\endgroup\$ – PlasmaHH Jul 28 '17 at 13:43
  • \$\begingroup\$ -1 for the completely useless title. That's where I stopped reading. \$\endgroup\$ – Olin Lathrop Jul 28 '17 at 13:52
1
\$\begingroup\$

But, shouldn't the last current (Iiii) go counterclockwise or it is optional?

If you drew the current one way and the result (after calculation) was a negative current then you know the arrow you drew was the wrong direction. It's a self-revealing thing and nothing to worry about.

\$\endgroup\$
0
\$\begingroup\$

Thank you, but, see:

enter image description here

The current I3 was negative and anyway it was left like that. Is it OK or the professor made a some kind of mistake?

\$\endgroup\$
  • \$\begingroup\$ It means the current is anti-clockwise. \$\endgroup\$ – Andy aka Jul 28 '17 at 17:55
0
\$\begingroup\$

In KVL and KCL theorems directions are chosen as the conventional as in your case all are clockwise so that when you go through the loop the current will be taken as 1-2 and which is traditional so as to not create any confusion. And by doing that whatever ans you may get if it had the negative sign then that shows it is reverse direction than what you've assumed. Same case happens for KCL, though we know that current will flow out of the supply but sometimes for convenience we take all currents are going outward from a node.

\$\endgroup\$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.