Charges `5.0 xx 10^(-7) C , -2.5 xx 10^(-7) Cand 1.0 xx 10^(-7) C` are
held fixed at the three corners A, B, C of equilateral triangle of side 10cm respectively. Find the electric force on the charge at C due to the rest two.

Explanation

To solve the problem of finding the electric force on the charge at point C due to the charges at points A and B, we will follow these steps:

### Step 1: Identify the charges and their positions
- Charge at A (QA) = \(5.0 \times 10^{-7} \, C\)
- Charge at B (QB) = \(-2.5 \times 10^{-7} \, C\)
- Charge at C (QC) = \(1.0 \times 10^{-7} \, C\)
- The side of the equilateral triangle (r) = 10 cm = \(0.1 \, m\)

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