## anonymous 4 years ago two electric devices A & B are connected in parallel and the rms current in A is 15 A. If the current in B lags behind A by pi/2 radians and the line current is 23.4 A. Determine the current in B

1. anonymous

|dw:1347318735842:dw| Load B Lags A by 90 degrees. The line is the resultant you Pythagorean theorem

$\sqrt{23.4^{2}-15^{2}}$

4. anonymous

why subtract?

5. anonymous

i get it why. lol

The line current is the resultant or the "total" In order to separate the total to the individual components, subtraction is the logical choice.

7. anonymous

so that is the current in B?

9. anonymous

another question, what is the difference between rms current and line current?

It is an inductive load when compared to the 15 amp load, or you could say the A is a capacitive load when compared to B. It is all relavent.

The line current is the combined currents of the two loads and is the current traveling to and fro from the power source. It is of course AC as we are talking RMS, all the currents in this problem is assumed to be measured in RMS units......including the line current.

Root Mean Square (RMS) is the most common value to measure AC, it is the value that DC current would produce as heat when the AC RMS value is converted to heat.

Kind of confusihng, but AC has several values of current/voltage. Peak Peak to Peak RMS (root mean square) Average

14. anonymous

ok. thanks a lot! :)

Good luck, are you pursueing an electrical engineering major?

16. anonymous

no. actually, my major is mechanical engineering, it's just that it's an elective course.

17. anonymous

are you ana electrical engineer?

Understand, good luck with it, and I think you are getting into a great field.

19. anonymous

thank you. :) hope i can make it. :)

Not a degreed EE, but an EE as far as the U.S. Government, I was a GS-855 for the FAA for years. There are other methods to become an engineer, but I recommend the method you are going, a formal education with a degree.

21. anonymous

i see. hail to all engineers. :)