1. Electric Current
Static electricity is the momentary movement of charged particles.
Current electricity is the continuous movement of charged particles in a path.
The moving particles are electrons.

2. Current (I)
a measure of how many electrons pass through a wire each second
the SI unit is the ampere (A)
current = amount of charge/ time interval
𝐼= 𝑄 𝑡 Q – amount of charge, unit is the coulomb (C)
t – time interval, unit is seconds (s)

3. A charge of 24C passes through a circuit in
Example
A charge of 24C passes through a circuit in
3 minutes. Calculate the current in the wire.
𝐼= 𝑄 𝑡
= 24𝐶 180𝑠
=0.13 𝐴
Electricity Video

4. Current and Elementary Charge
Robert Milikan discovered that the charge on one proton or electron is 1.6 x C
he called this the elementary charge (e)
the amount of a charge (Q) can be found by finding the product of the number of elementary charges (N) and the magnitude of the elementary charge (e)
𝑄=𝑁𝑒

5. Example
Calculate how many electrons passed through a light bulb that has a charge of 320 C. 𝑄=𝑁𝑒 320=𝑁1.6 x 10−19 N =2.0 𝑥 1021 electrons 12.3 Prac. #1-5 UC #1-6