1.
Within a circuit, there are tiny positive charges that are free to move 1 . What do you think is happening to all of those tiny positive charges in a simple circuit with a battery and a light bulb?
Section 10.5 Electric Current
Exercises Warm-up Activity
The voltages across different elements of a circuit produce electric fields within the elements that help move the charges along, producing a current.
Definition 10.5.1. Electric Current.
Electric Current is the flow of electric charge and has units of Amps (\(\mathrm{C}/\mathrm{s}\)). It is defined as the rate of positive charge flowing past a given point in a circuit per unit time:
\begin{equation*}
I = \frac{dq}{dt}
\end{equation*}
Exercises Activities
1.
Recall the circuit (Figure 10.2.1) from Section 10.2. Do you think that the current passing through element B is greater than, less than, or equal to the current passing through element A? Explain your answer.
in fact, it is the negative charges that are free to move, but it is conventional to consider the positive charges instead
