Question

Charge on a body A is 5C and Body B is also 5C. If both the bodies are identical, then
a) Electron will flow from A to B , when they are brought in contact
b) electrons will flow from B to A, When they are brought in contact
c) Electrons will flow from A to B first and B to A Later. When brought in contact
d) No flow of electrons, if they brought in contact

Answer 1

Explanation:

Correct option is

B

II only

The electrostatic force between two charges q=2e and q=2e , separated by a distance r is ,

F=K

r

2

2e×2e

=K4e

2

/r

2

,

after transfer of charge , new charge distribution is q=e and q

′

=3e , now ,electrostatic force between them will be ,

F

′

=K

r

2

e×3e

=K3e

2

/r

2

,

this implies F

′

<F , force between them decreases.

Total charge before transfer =2e+2e=4e

and total charge after transfer =e+3e=4e ,

It remains the same .

thank you