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Circuit Element Explanation

Source Transformation

Source transformation changes the shape of a source circuit without changing what the load sees.

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Circuit Element ModelUse the explanation below for this element only.

Explanation

  • A voltage source with series resistance can become a current source with parallel resistance.
  • It is used to simplify circuits before solving.
  • The outside terminals behave the same, even though the inside drawing looks different.

Formula

I = V / R

  • I is the equivalent current source value.
  • V is the original voltage source value.
  • R is the same resistance used in the transformation.

Key Idea

Source transformation changes circuit form while keeping terminal behavior the same.

Visual Explanation Steps

Show a voltage source and series resistor morphing into a current source and parallel resistor.

Step 1

Original Source Form

Start with a voltage source in series with a resistance.

Step 2

Convert Source Value

Use I = V / R to find the equivalent current source value.

Step 3

Equivalent Source Form

Draw the current source with the same resistance in parallel.

Step 4

Same Terminal Behavior

The outside load sees the same voltage-current behavior, even though the internal form is different.