Which type of electric charge is primarily responsible for holding small dust particles together in space through electrostatic attraction?

• A. Neutral particles are held together by electric charge.
• B. Only $-$ electric charges can hold particles together in space.
• C. Only $+$ electric charges can hold particles together in space.
• D. Opposite electric charges, such as $+$ and $-$, attract and hold the particles together.

Answer: (D)

Verified step by step guidance

1. Understand that electrostatic attraction occurs between opposite electric charges, meaning positive (+) and negative (-) charges attract each other.
2. Recognize that small dust particles in space can acquire electric charges through various processes such as photoelectric effects or collisions, leading to some particles becoming positively charged and others negatively charged.
3. Recall the fundamental principle that like charges repel each other, while opposite charges attract, which is the basis for electrostatic forces holding particles together.
4. Apply Coulomb's law, which quantifies the electrostatic force between two charges: \(F = k \frac{|q_1 q_2|}{r^2}\), where \(q_1\) and \(q_2\) are the charges and \(r\) is the distance between them, showing that opposite charges exert an attractive force.
5. Conclude that the primary mechanism holding small dust particles together in space through electrostatic attraction is the presence of opposite electric charges on the particles.