Traffic Jams, Resistance
Picture Source: http://www.clker.com/cliparts/d/4/e/5/11954427991094287987ryanlerch_Roadlayout_sign_9.svg.med.png
Dictionary.com defines resistance as "a property of a conductor by virtue of which the passage of current is opposed, causing electric energy to be transformed into heat." Any resistance to the current flow is counted as resistance. This brings up Ohm's law which is
V = I*R, or voltage is current multiplied by the resistance. In a circuit, if you know any two of those parameters then you can calculate the third.
If these negative people on their way to the depressing concert meet anything that slows them down then they are going to get real mad. The more they are slowed the more angry they get. An example could be that a five lane road is narrowed to three lanes because two of them are under construction. This causes a traffic jam slowing the current of cars going through. The traffic jam, however, has no effect on their desire to go to the concert. The people are still just as exited to go.