Wednesday, May 19, 2010

Don't Let it Catch on Fire!

      On my first try on the simulation, my battery and switch caught on fire.  This is because the negative part of my light bulbs were not connected to any part of the wires.  A DC circuit must be connected by wires to the positive and negative sides of the battery. 

      The picture on the right resembles a typical series circuit.  It involves three light bulbs, a battery, and a switch.  In a series circuit, the current is the same throughout the wires.  All of the light bulbs in a series circuit have the same amount of voltage.  If one light bulb is unscrewed, they all turn off.

The picture on the right resembles the typical parallel circuit.  There are three parallel wires, each with a light bulb, and a battery.  The current through each wire is the same.  The voltage through each wire depends on the resistance of the light bulb.  If one light bulb were unscrewed, the others would still be on.

The picture on the right resembles a typical complex circuit.  It involves a parallel circuit and a series circuit.  The resistance is the equivalent resistance of the parallel circuit plus the resistance of the lone light bulb in the series.  The voltage of the series circuit bulb is greater than a light bulb in the parallel circuit.

1 comment:

  1. Great diagrams, especially the first one as it clarifies how a circuit must be connected. However, you did not clearly explain the two characteristics of DC circuits.
    There are some incorrect statements in your posting. First, you said that the voltage goes through through the circuit, that is incorrect, voltage is the potential difference ACROSS an element in a circuit.
    In the parallel circuit you said that the current through each wire is the same. That is incorrect as the electrons now have two different paths to flow through. This would be the case only through each parallel branch if and only if the resistances are equal. But the current in other points of the wire is not the same.
    The assignment required a detailed explanation of how current and voltage works in each circuit and this is missing especially in your third circuit.
    Please be sure that you understand how the circuits work as it is an important part of the final exam.