Two poles of the same strength attract each other with a force of magnitude F when placed at two corners of an equilateral triangle. If a north pole of the same strength is placed at the third vertex, it experiences a force of magnitude

Refer to Fig. Let a north pole be placed at B and a south pole at C so that they attract with a force F. A north pole placed at the third vertex A is repelled with a force by the north pole at B and attracted with a force
towards the south pole at C. Since all pole strengths are equal,
. The resultant force experienced by the north pole at A is given by
or , which is choice (b)
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5 g of Na2SO4 was dissolved in x g of H2O. The change in freezing point was found to be 3.820C. If Na2SO4 is 81.5% ionised, the value of x (K

A capacitor is made of two square plates each of side 'a' making a very small angle
A solution of m-chloroaniline, m-chlorophenol and m-chlorobenzoic acid in ethyl acetate was extracted initially with a saturated solution of NaHCO3 to give fraction A. The leftover organic phase was extracted with d