Question 849: Electrostats & Capacitance

Question

Select the correct statement from the following.

Accepted Answer

The correct option is:
Option C: Gravitational as well as electrostatic force always act along the line joining the two objects.
Explanation:
Option A is incorrect because gravitational force is actually much weaker than the electrostatic force. The gravitational force between two particles is given by Newton's law of gravitation:
$$
F_{	ext{gravity}} = G \frac{m_1 m_2}{r^2}
$$
where $ G $ is the gravitational constant, $ m_1 $ and $ m_2 $ are the masses of the particles, and $ r $ is the distance between their centers. On the other hand, the electrostatic force is given by Coulomb's law:
$$
F_{	ext{electrostatic}} = k \frac{|q_1 q_2|}{r^2}
$$
where $ k $ is Coulomb's constant, and $ q_1 $ and $ q_2 $ are the electric charges of the particles. The electrostatic force is much stronger than the gravitational force because the gravitational constant $ G $ is a much smaller number than Coulomb's constant $ k $.
Option B is incorrect because the electrostatic force can be either attractive or repulsive, depending on whether the charges are opposite (attractive) or like charges (repulsive). However, the gravitational force is always attractive, as it always acts to pull masses together.
Option C is correct. Both gravitational and electrostatic forces act along the straight line joining the centers of the two masses or charges, respectively. This line is known as the line of action for these forces.
Option D is incorrect because the electrostatic force does indeed obey an inverse square law, just like the gravitational force. Both forces diminish in strength with the square of the distance between the two objects, as is reflected in the equations for both forces (Newton's law of gravitation and Coulomb's law).

Answer

Gravitational force is stronger than electrostatic force

Answer

Gravitational as well as electrostatic force always attractive.

Answer

Gravitational as well as electrostatic force always act along the line joining the two objects.

Answer

Inverse square law $$\left(\mathrm{F} \propto \frac{1}{\mathrm{r}^2}\right)$$ is not obeyed by electrostatic force.

Electrostats & Capacitance

Select the correct statement from the following.

Choose the correct answer: