Help if you can. Please

[markthespark]

I am studying at college for the C&G 2330 level 3 and am about to take my 301 exam tomorrow and have come accross a question in some sample questions i cant seem to fathom maybe someone can help as i cant find the formula or formulas for answering it. Maybe i Missed that lesson. The quetion goes like this: A capacitor of 100uF is connected in parrallel with a 20 ohm resistor. The group is connected to a 200v 50 hz supply. Calculate the power dissipated in the combination? Possible answers are 2000W, 2400W, 3000W, or 3600W. I know the answer is 2000W but how do you get at this?

 

[springcrocus]

I think you will find that the capacitor in parallel is a red herring - a capacitor is a wattless volt-dropper - so, for power calcs, it can be ignored.

Using Ohm's law, I = V / R so I = 200 /20 = 10

Power law says P = V x I so P = 200 x 10 = 2000

 

[markthespark]

Wow thanks. i feel such a fool.

 

[Doc Hudson]

Wow thanks. i feel such a fool.

Welcome to the forum markthespark, no one is fool for asking a question that they don't know the answer to. This is one of the reasons the forum is here. Ask find out, debate, discuss, all learn together, without all of the unhelpful answers received on some other forums.

Doc H.