Question 842: Electrostatics & Capacitance

Question

Which of the following statement(s) is/are correct?

Accepted Answer

Gauss's law is valid only if Coulomb's law holds, i.e. if $$E \propto {r^{ - 2}}$$. Hence, choice (a) is wrong. Gauss's law cannot be used to calculate a non-uniform field distribution around an electric dipole. So choice (b) is also wrong.
Choice (c) is correct because the directions of electric fields are opposite at a point between two similar charges.
Work done $${W_{A 	o B}} = q({V_B} - {V_A}) = ({V_B} - {V_A})$$ ($$\because$$ $$q =  + \,1\,C$$)
Hence, choice (d) is correct.
So the correct choices are (c) and (d).

Answer

If the electric field due to a point charge varies as $${r^{ - 2.5}}$$ instead of $${r^{ - 2}},$$ then the Gauss law will still be valid.

Answer

The Gauss law can be used to calculate the field distribution around an electric dipole.

Answer

If the electric field between two point charges is zero somewhere, then the sign of the two charges is the same.

Answer

The work done by the external force in moving a unit positive charge from point $$A$$ at potential $${V_A}$$ to point $$B$$ at potential $${V_B}$$ is $$\left( {{V_B} - {V_A}} \right).$$

Electrostatics & Capacitance

Which of the following statement(s) is/are correct?

Choose the correct answer: