Question

four charges are arranged at the corners of a square ABCD of side d. find the work required to put together this arrangement.
A charge q0 is brought to the centre E of the square, the four charges being held fixed at its corners. how much extra work is needed to do this?

Answer 1

Work done = PE
 
PE = 1/(4πε₀)× q₁q₂/ r₁

W= 0 + (-1/(4πε₀) × q²/a) +((-1/(4πε₀) × q²/a) + (-1/(4πε₀) × q²/a√2)) +((-1/(4πε₀) × q²/a)+(-1/(4πε₀) × q²/a√2) + (1/(4πε₀) × q²/a))

= (-4/(4πε₀) × q²/a) + (2/(4πε₀) × q²/a√2)

=1/(4πε₀) × q²/a × ((√2)- 4)

Potential at the center of square: V=0

W=q₀ V = 0

Hope my answer is helpful to u.

Answer 2

Answer:

-2.6kq^2/a

Explanation:i think this is correct answer and question in the image given by me

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