Skip to content
UPEEC

Charge and Current

Electric current is the rate at which charge flows past a point.

Beginner
Comments 0

Charge comes in discrete amounts: one electron carries −1.602×10−19-1.602 \times 10^{-19} C. Current is the flow rate of charge:

I=dQdtI = \frac{dQ}{dt}

One ampere is one coulomb per second (about 6.24×10186.24 \times 10^{18} electrons per second).

By convention conventional current flows from + to −, the opposite direction to electron flow. Circuit diagrams always use conventional current.

  • DC (direct current) flows in one direction.
  • AC (alternating current) reverses direction periodically.

Spotted a mistake or want to add detail? Suggest an improvement — Content Contributors' edits are reviewed by editors before they go live.

Discussion (0)

Sign in or join free to ask questions and discuss this topic.