Ohm's Law (DC Circuit)
Close a simple battery-and-bulb loop — adjust the source voltage and resistance to see the current and power follow Ohm's law exactly, with the bulb brightness and charge-flow dots tracking the result live.
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What you can adjust
- Source voltage (V)
- 1 – 24 V
- Resistance (R)
- 1 – 100 ohm
The DC EMF driving the loop — 9V is a common real battery voltage.
Ohm's law: I = V/R. Bigger resistance means less current for the same voltage — try dragging it up and watch the bulb dim and the charge-flow dots slow down.
About this simulation
What it shows
A battery drives current through a bulb in a simple loop. The current and power are read out while charge-flow dots and the bulb's brightness follow the result.
The key idea
Current equals voltage divided by resistance (I = V/R), and the power used is P = V × I. More resistance means less current for the same voltage.
Try this
Double Resistance (R) from 10 to 20 ohm: the current halves from 0.9 A to 0.45 A, the dots slow down and the bulb dims.