•           Symbol: V

•           Unit: Volt

Ø    Potential difference across two terminals in a circuit “across variable.”
Ø    In order to move the charge from point A to point B, work needs to be done.
Ø    Like potential energy at a waterfall.
Ø    Let A be the    lower   potential/voltage terminal
Ø    Let B be the    higher  potential/voltage terminal

Then, the voltage across A and B is the cost in energy required to move a unit positive charge from A to B.

Voltage-Water Analogy

    Series Connection of Cells

• Each cell provides 1.5 V
• Two cells connected one after another, in series, provide 3 V, while three cells would provide 4.5 V
• Polarities matter

Parallel Connection of Cells

• If the cells are connected in parallel, the voltage stays at1.5 V, but now a larger current can be drawn.

Wire-Water Analogy