# Nodal Analysis and Power consumption

Discussion in 'Homework Help' started by Intrud3r, Mar 9, 2009.

1. ### Intrud3r Thread Starter New Member

Mar 9, 2009
2
0
Hi, i've been posed the following question:

From nodal anlysis i obtained v1=15 v2=v=5 v3=-20

Does that mean v3 is supplying the voltage through the circuit?!? Also could you check to see if those values are correct.

Also how am i supposed to be able to calculate the power associated with the dependant power source. Does the - value mean it is being delivered to the circuit and that and that the 15V power source is actually absorbing the power?

for part c) is the power value 37.5W, and is it being delivered? as it is a positive value?

Any insight into this problem would be much appreciated. Also what is the answers to each section, a) b) c) etc. as i am absolutely stumped.

Regards
Thomas Introna

2. ### hgmjr Retired Moderator

Jan 28, 2005
9,029
219
If you calculated v = 5, shouldn't the dependent voltage source be 5*v which equals 25 volts?

hgmjr

3. ### vvkannan Active Member

Aug 9, 2008
138
11
Hi Intrud3r,
I get the same values as you have got .

Now you know all the voltages (hence the current)

Calculate the power across the resistors and add them

Calculate the power across 15 v source.(15 x 2).
This is less than the power drawn by resistors. Hence the dependent source supplies the remaining power