Key idea
Electric potential
V = kQ/r · ΔU = qΔV
Start with the central idea, then test it against a concrete element or example. A scientific model is useful when we know what it explains — and where its limits are.
Electric potential
The key idea
Electric potential is potential energy per unit charge. Potential differences tell us how much electric potential energy changes per unit charge between two points.
Why it matters
Voltage is therefore not a substance flowing through a wire; it is a difference in electric potential.
A picture to remember
Key idea
Electric potential
Guided example
Electric potential
Start with the central idea, then test it against a concrete element or example. A scientific model is useful when we know what it explains — and where its limits are.
Put it into practice
Electric potential
Choose a concrete case linked to Electric potential. Write down the known information, what you are trying to find, and the units. Then state the rule, model or trend you will use. If a calculation is involved, keep the units visible at every line; if it is conceptual, state what changes and what remains fixed.
Check your answer
A strong answer contains four things: the starting situation, the variable that changes, the direction or numerical result, and one check. The check can be a unit, an order of magnitude, a limiting case or a comparison with a familiar example.