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C1 and C2 are two hollow concentric cubes enclosing charges 2Q and 3Q respectively as shown in figure. The ratio of electric flux passing through C1 and C2 is : [figure]
(3) 2:5
Gauss's law: = qenclosed 0 (independent of the shape and size of the closed surface)
Inner cube C1 encloses only 2Q ⇒ 1= 2Q 0
outer cube C2 encloses both charges ⇒ 2= 2Q+3Q 0= 5Q 0
1: 2=2:5
Answer: (3)
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