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It's Time for some PHYSICS Analogy!

 Hello Readers,



An analogy can be drawn between different conservation laws. Observe the similarity in various quantities listed below.




Example:

N identical drops of mercury are charged simultaneously to a potential of 10 V. When combined to form one larger drop, the potential is found to be 40 V. The value of N is

[Options]:

(A) 5

(B) 3

(C) 8

(D) 10

Answer: (C)

Let r be the radius of each drop and R be the radius of the larger drop. The volume of N identical drops is equal to the volume of the larger drop.



Let q and Q be the charges on the small drops and the larger drop respectively.

From the law of conservation of electric charge,



The potential of a small drop is



The potential of the larger drop is



Divide equation (3) by equation (4).



Substitute the known values.

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