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Force between two point charges q1 and q2 placed in vacuum at 'r' cm apart is F. Force between them when placed in a medium having dielectric constant K=5 at 'r/5' cm apart will be:
(1) 5F
F= 14 0 q1q2r2, in a medium F'= 14 0K q1q2r'2
K=5 and r'= r5
F'F= 1K ( rr' )2= 255=5
F'=5F
Answer: (1)
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