Question

Which of the following statements is impossible to verify in the experience? (Note that the problem does not say anything about the sign of the charges, it is at your discretion to assign the possible signs)

a) three electric charges repel each other

b) three electric charges attract each other

c) two of the three charges repel each other but both are attracted by the third charge

d) alternatives (a), (b) and (c)

e) none of the above

Answer 1

We know from Coulomb's law

the force of attraction or repulsion between two charges is

F = k*q1*q2/r^2

and the same kind of charges are repeles each other and

opposite charges always attracts each other

if the third charge is there near by the two charges infact in the vicinity of the electric field of the two charges depends on the polarity of the charge the third charge may be repel or may be attracted by any one of the charges

if all the three charges are of same kind they repel each other

but the second statement is not possible

because the three electric charges attract each other

is impossible , if there must be attractive force between two charges there must be of different polarity charges

so the answer is option b