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Electricity & circuits
A battery pushes electrons. A resistor slows them. A bulb turns the push into light. Three numbers, one law: V = I · R.
Ohm's law circuit
More volts → faster electrons → brighter bulb.
Voltage6 V
Resistance3 Ω
Current I: 2.00 A
Power: 12.00 W
V = I · R · P = V · I
The water pipe analogy
- Voltage is the pressure pushing water.
- Current is how much water flows per second.
- Resistance is how narrow the pipe is.
- The bulb is a paddle wheel — it lights up when water spins it.
Ohm's law
V = I · R — pressure equals flow times pipe-narrowness. Rearrange it: I = V / R. Double the voltage, current doubles. Double the resistance, current halves.Power: how fast it does work
P = V · I. A 60-watt bulb turns 60 joules of electrical energy into light and heat every second. The bulb in the simulation glows brighter when power is higher.
Series vs parallel
- Series — components in a single loop. Current is the same everywhere; voltage divides up.
- Parallel — components on side branches. Voltage is the same; current divides up.