Question

Assertion :If a conductor is given charge then no excess inner charge appears. Reason: Electric field inside conductor is zero.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
• C. Assertion is correct but Reason is incorrect.
• D. Both Assertion and Reason are incorrect.

Answer 1

Answer: (A)

In electrostatic case, conductors do not permit electric field lines to pass through them. As long as there is electric field inside the conductor, electrons would move so as to neutralise this field. Thus, an induced electric field essentially develops inside the conductor which cancels out the applied external electric field.

Any excess charge, if it were present inside the conductor material, would create a field of its own, which would soon be neutralised by motion of electrons. But as conservation of charge holds everywhere, the excess charge must then appear at the surface of the conductor.

Thus, assertion and reason are both correct and reason is the correct explanation for assertion.