AP currents labs

A large number of you are laboring under serious misconceptions. Currents flow in circuits because fields are created in conductors which cause the electrons present in the conductors to gain small average velocities. The amount of current that flows depends on the field and on how many electrons are available to move and how easily they can move. The field , in turn, is determined by how much voltage difference is placed across the conductor. Thus the amount of current that flows depends on the nature and geometry of the conductor and the voltage across it. The total current in a circuit is DEFINTELY NOT some fixed quantity, it IS dependent on the number of conductors available to carry it.

Batteries impose a voltage difference across a circuit. The current arises in response to this voltage difference and, once again, depends on the number and quality of the conductors experiencing the voltage. By removing a parallel resistor you have removed a conductor (resistors are just imperfect conductors) and thus reduced the total current. If the voltage remains the same, each remaining parallel elements will carry its own original current. If the voltage available to these elements rises, as it sometimes does because the lower total current reduces voltage losses elsewhere in the circuit, there will be an increase in the current in the remaining elements, but this is NOT because the current from the removed element has to find somewhere to go. The current that was flowing in the removed element simply ceases to exist because the electrons that were flowing in that element are no longer in the circuit.