A Level Physics Practice Exam

Which of the following correctly represents the relationship between protons and neutrons?

1. Protons are heavier

2. Both are negatively charged

3. Neutrons have no charge

4. Protons can vary in mass

The correct answer is: Neutrons have no charge

The option highlighting that neutrons have no charge accurately reflects the fundamental properties of these subatomic particles. Neutrons are found in the nucleus of an atom alongside protons, and they play a crucial role in stabilizing the nucleus. Since they possess no electric charge, neutrons do not contribute to the electrical interactions that occur between charged particles, such as protons and electrons. In contrast, protons are positively charged, and the existence of charge is a significant factor in the behavior of atoms and their interactions. This property drives chemical bonding and the formation of various atomic structures. The other options introduce misconceptions. Protons and neutrons are roughly the same mass, with slight differences but not significant enough to categorize protons as heavier. Moreover, both protons are positively charged, while neutrons carry no charge. Lastly, protons do not vary in mass; their mass is a defining characteristic of an element and remains constant for all protons. Understanding these distinctions is essential for grasping atomic structure and interactions.