Question

Four charges are placed at the corners of a square a side 'a' find tge net force on the charge at the corner c

Answer 1

Answer:

(√2 + 1/2) kq²/a²

Explanation:

  Using, force(electrostatic) = kq₁q₂/r²

Here, q₁ = q₂ = q     ; r = a and,  r = a√2 for A-C(using Pythagoras theorem)

   Thus,

Force by A = k qq/(a√2)² = k q²/2a²

Force by B = k qq/a² = k q²/a²

Force by D  = k qq/a² = k q²/a²

Using vector addition, resultant is

     = √F(B)² + F(D)² + F(B).F(D)cos90

     = √(kq²/a²)² + (kq²/a²)² + 0

     = √2 (kq²/a²)

We add the resultant force and force by A, since both are in same line(direction).

Force on C = √2 (kq²/a²) + (kq²/2a²)

                  = (√2 + 1/2) kq²/a²