Assertion and reason

Exercise and reference answers

Questions

1. Reason

   There n is so large that the granularity of e is undetectable.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Quantisation of charge can be ignored for macroscopic bodies.

2. Reason

   Charge is transferred between the bodies, not created.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   Charging by friction does not violate conservation of charge.

3. Reason

   The net force on a charge is a vector sum over all pairs.

   Verdict

   The assertion is false and the reason is true.

   Assertion

   A third charge alters the force between the first two.

4. Reason

   Their ratio for a proton and electron is about 2.4 × 10³⁹.

   Verdict

   Both are true; the reason explains the assertion.

   Assertion

   The electric force dwarfs gravity inside an atom.

Explanation