⚑ Electric Circuits

Ohm's Law Β· series & parallel Β· power Β· circuit theory

⚑ Ohm's Law Calculator

Enter any two values and the third is calculated automatically. Ohm's Law states that voltage equals current multiplied by resistance.
V = I Γ— R
Enter two values above to calculate the third

β†’ Series Resistance Calculator

In a series circuit, resistors are connected end-to-end. The total resistance is simply the sum of all resistors. Current is the same through every component.
Rtotal = R₁ + Rβ‚‚ + R₃ + …
Enter resistor values in ohms (Ξ©) β€” up to 6 resistors:
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Series circuit facts:
β€’ Same current flows through every component
β€’ Total voltage is split across components (proportional to resistance)
β€’ Total resistance is always greater than any individual resistor
β€’ If one component breaks, the entire circuit stops working

β«Έ Parallel Resistance Calculator

In a parallel circuit, resistors provide multiple paths for current. Total resistance is always less than the smallest individual resistor.
1/Rtotal = 1/R₁ + 1/Rβ‚‚ + 1/R₃ + …
Enter resistor values in ohms (Ξ©) β€” up to 6 resistors:
β€”
Parallel circuit facts:
β€’ Same voltage across every branch
β€’ Current splits between branches (inversely proportional to resistance)
β€’ Total resistance is less than the smallest resistor
β€’ Adding more branches increases total current (lowers total resistance)
β€’ If one branch fails, the others keep working β€” used in home wiring

πŸ’‘ Power Calculator

Electrical power is the rate of energy transfer. Enter voltage and current to calculate power, or any two of the three values.
P = V Γ— I = IΒ² Γ— R = VΒ² / R
Enter voltage and current to calculate power
πŸ”‹
Voltage (V)
The electrical "pressure" that drives current through a circuit. Measured in volts (V). Like water pressure in a pipe β€” higher voltage pushes more current. Sources: batteries, power supplies, generators.
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Current (I)
The flow of electric charge through a conductor. Measured in amperes (amps, A). Like water flow rate through a pipe. DC (direct current): flows one way. AC (alternating current): reverses direction rapidly (50–60 Hz).
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Resistance (R)
Opposition to the flow of current. Measured in ohms (Ξ©). All conductors have some resistance. Resistors are components designed to provide specific resistance. Thin wires have more resistance than thick wires.
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Power (P)
The rate at which electrical energy is converted to another form (heat, light, motion). Measured in watts (W). A 60W bulb uses 60 joules per second. Energy (joules) = Power Γ— Time.
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Kirchhoff's Laws
KCL: The sum of currents entering a node equals the sum leaving it (charge conservation).
KVL: The sum of all voltages around any closed loop equals zero (energy conservation).
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Capacitors & Inductors
Capacitors store energy in an electric field (like tiny rechargeable batteries). Inductors store energy in a magnetic field (coils of wire). Together they enable AC circuits, filters, oscillators and transformers.
What is this?

An electric circuit is a closed path through which electric current can flow. Circuits contain components like batteries, resistors, and bulbs arranged in series or parallel configurations.

Why does it matter?

Every electronic device β€” phones, computers, lights, appliances β€” is powered by circuits. Understanding them is fundamental to electronics, electrical engineering, and physics.

Key terms
Voltage (V) β€” the electrical pressure driving current; measured in Volts Current (I) β€” the flow of electric charge; measured in Amperes (A) Resistance (R) β€” opposition to current flow; measured in Ohms (Ξ©) Ohm's Law β€” V = IR; the core relationship between voltage, current, and resistance Series β€” components connected end-to-end; one path for current Parallel β€” components on separate branches; current has multiple paths
🎯 Try this challenge

Set voltage to 9V and resistance to 3Ξ© in the simulator. What current flows? Verify with Ohm's Law: I = V Γ· R. Now double the resistance β€” what happens to the current?

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