Assertion and reason

Exercise and reference answers

Questions

1. Reason

   A revolving electron accelerates, so it should radiate and spiral inward.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Rutherford's model contradicts the stability of matter.

2. Reason

   They allow an electron to revolve without radiating energy away.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Bohr introduced stationary orbits.

3. Reason

   An atom as a whole is electrically neutral.

   Verdict

   The assertion is false and the reason is true.

   Assertion

   Thomson's model has a nucleus.

Explanation