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Find the potential energy of a system of four identical particles placed at the vertices of a square of side l. Also obtain the potential at the centre of the square. |
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Answer» tem can be made by bringing each charge from REFERENCE (∞) and placing them on the vertices of the squareThen net work done in arranging the system = Potentital energy of teh system For bringing 1st charge : W 1 =0For bringing 2nd charge : W 2 l 2 kqq (ASSUMING each charge = q and SIDE = l)For bringing 3rd charge : W 3 = l 2 kqq + ( 2 l) 2 kqq For bringing 4th charge: W 4 = l 2 kqq + l 2 kqq + ( 2 l) 2 kqq Hence total work done = W 1 +W 2 +W 3 +W 4 = l 2 5kq 2 i.e. potential energy of system The potential at centra = 4× ( 2 1 ) 2 KQ = l 2 8kq |
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