Question 13

Suppose the spheres A and B in Exercise 1.12 have identical sizes. A third sphere of the same size but uncharged is brought in contact with the first, then brought in contact with the second, and finally removed from both. What is the new force of repulsion between A and B?

Answer

Distance between the spheres, A and B, r = 0.5 m

Initially, the charge on each sphere, q = 6.5 × 10 ^{−7} C

When sphere A is touched with an uncharged sphere C, q/2 amount of charge from A will transfer to sphere C. Hence, charge on each of the spheres, A and C, is q/2.

When sphere C with charge q/2 is brought in contact with sphere B with charge q, total charges on the system will divide into two equal halves given as,

1/2 (q + q/2) = 3q/4

Hence, charge on each of the spheres, C and B, is 3q/4.

Force of repulsion between sphere A having charge q/2 and sphere B having 3q/4 charge is

Therefore, the force of attraction between the two spheres is 5.703 × 10^{ −3} N.

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Swati
2019-07-06 06:43:30

Thanks

Shree
2019-06-20 19:33:29

Sorry this write

Shree
2019-06-20 19:27:23

This is wrong

Anant Dhillon
2019-04-14 22:37:21

This answer is well defined. Thanks for it.

Sohail
2018-10-31 19:32:16

Sorry this is write

Sohail
2018-10-31 19:30:58

This is wrong

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