Electric Current

What is Current?

Current is the flow of electric charge (electrons) through a conductor, like a wire. It’s similar to the flow of water through a pipe.

  • Unit of Current: Ampere (A)
  • Symbol for Current: I

Real-Life Example: Water Flow in a Pipe

Imagine you have a water tank connected to a pipe with a tap at the end.

🔹 The water pressure inside the tank represents voltage (the force pushing water).
🔹 The pipe represents the wire (the conductor where electrons move).
🔹 The flow of water through the pipe represents current (the movement of electrons).

➡️ When you open the tap, water flows — just like current flows when a circuit is closed.
➡️ The stronger the water pressure, the more water flows — just like higher voltage pushes more current.


Key Observations in This Example:

1️⃣ Narrow Pipe = Less Current: A thin pipe restricts water flow, just like a small wire restricts current flow.
2️⃣ Wide Pipe = More Current: A wider pipe allows more water flow, just like a thick wire can carry more current.
3️⃣ Closed Tap = No Current: If the tap is closed, no water flows — similar to an open circuit with no current.
4️⃣ More Pressure = Higher Current: Increasing water pressure (voltage) increases water flow (current).


Example in Electrical Systems:

Imagine a 220V home circuit:

  • When you plug in a 100W bulb, a small current flows.
  • When you plug in a 2000W heater, a much larger current flows.

✅ More electrical devices = More current flow.
✅ Thicker wires are required for high-current appliances to avoid overheating (just like a wider pipe for higher water flow).


Quick Formula to Remember:

I = V / R
Where:

  • I = Current (in Amperes)
  • V = Voltage (in Volts)
  • R = Resistance (in Ohms)

Summary:

✅ Current is like water flow in a pipe.
✅ Higher voltage pushes more current.
✅ Thicker wires are like wider pipes — they allow more current to pass safely.

Explore the basics to become more knowledgeable. Let’s Go!

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