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+--- Thread: Ohm’s Law — How Electricity Actually Flows (/showthread.php?tid=408)
Ohm’s Law — How Electricity Actually Flows - Leejohnston - 01-08-2026
## Ohm’s Law — How Electricity Actually Flows
### 1. The Equation
V = I × R
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### 2. What Each Symbol Means
- V = voltage (volts)
- I = current (amps)
- R = resistance (ohms)
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### 3. What the Equation Is Telling Us
Ohm’s Law describes how easily electric current flows through a circuit.
- Higher voltage → more push
- Higher resistance → more opposition
- Current is the result of both
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### 4. Where It Comes From (Intuition)
Think of electricity like water in a pipe:
- Voltage = pressure
- Current = flow rate
- Resistance = pipe narrowness
More pressure or a wider pipe → more flow.
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### 5. Worked Example
If:
- Voltage = 12 V
- Resistance = 6 Ω
Current = V ÷ R
= 12 ÷ 6
= **2 amps**
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### 6. Real-World Applications
- Electronics design
- Fuse ratings
- Power supplies
- Battery safety
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### 7. Common Mistakes
- Forgetting units
- Mixing AC and DC concepts
- Assuming resistance never changes
---
### Try It Yourself
What happens to the current if:
- resistance doubles?
- voltage is halved?