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How to Calculate Electrical Electronics

What is Electrical Electronics?

Electrical and electronics calculators cover resistor selection, circuit analysis, power calculations, and component sizing. They are used by hobbyists, technicians, and engineers designing circuits.

Step-by-Step Guide

  1. 1LED resistor: R = (Vsupply − Vforward) / I_forward
  2. 2Voltage divider: Vout = Vin × R2 / (R1 + R2)
  3. 3Power factor: PF = real power (W) / apparent power (VA)

Worked Examples

Input
5V supply · LED Vf = 2.0V · If = 20mA
Result
R = (5 − 2) / 0.02 = 150 Ω (use 150 Ω standard value)
Always round up to the nearest standard resistor value

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