For the circuit below, calculate the power absorbed by each source,

For the circuit below, calculate the power absorbed by each source, and verify that the powers add to zero. Solution Power absorbed by 3A source: since this source is in parallel with the 10V source, and the current flows into the negative terminal, P = 3A * 10V = 30W Power absorbed by -4A source: since this source is in parallel with the 10V source, and the current flows into the positive terminal, P = -(-4A * 10V) = 40W Power absorbed by 2A source: split this one into two, considering both voltage sources: current flows into positive terminal of 10V source, so P = -(2A * 10V) = -20W current flows into negative terminal of 8V source, so P = 2A * 8V = 16W total power absorbed is P = -20W + 16W = -4W Power absorbed by 8V source: since this source is in series with 2A source, and the 2A flows into the negative terminal, P = - (2A * 8V) = -16W Power absorbed by 10V source: split this one into two, considering two current sources: 3A current source flows into negative terminal, so P = -(3A * 10V) = -30W The other current flowing into this source can be found by applying KCL on the node that connects the 2A and -4A source. Since there is 2A + (-4A) = -2A flowing into that node, there must be -2A flowing out of that node and into the positive terminal of the 10V source. Therefore, P = -2A * 10V = -20W total power absorbed is P = -30W + (-20W) = -50W Add the power absorbed by all sources: 30W + 40W + (-4W) + (-16W) + (-50W) = 30W + 40W - 4W - 16W - 50W = 0