Difficulty: Easy
Correct Answer: An electron has a negative charge and a proton has a positive charge
Explanation:
Introduction / Context:Understanding the fundamental charges of subatomic particles is a cornerstone for electricity, electronics, and chemistry. Charge polarity determines how particles interact in electric fields, how current flows, and why materials behave as conductors, insulators, or semiconductors.
Given Data / Assumptions:
Concept / Approach:By definition, electrons carry a unit negative charge while protons carry an equal-magnitude positive charge. Neutrons are electrically neutral. Because the magnitudes are equal, a neutral atom has equal numbers of electrons and protons, balancing total charge to zero.
Step-by-Step Solution:
1) Recall the standard charges: electron = negative, proton = positive.2) Compare magnitude: both have equal magnitude of charge, but opposite signs.3) Determine the correct descriptive statement: electron (negative) and proton (positive).Verification / Alternative check:Charge conservation and electrostatic attraction of unlike charges (electron–proton) confirm the polarity assignment used throughout physics and electronics.
Why Other Options Are Wrong:
Electron positive / proton negative: reverses the true polarities.Electron or proton with no charge: incorrect; that describes a neutron, not an electron or proton.None of the above: unnecessary because the correct pairing is available.Common Pitfalls:Confusing the sign convention or assuming charge depends on location in the atom; polarity is intrinsic to the particle type.
Final Answer:An electron has a negative charge and a proton has a positive charge.
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