Nursing Elites

1. Which of the following is the antiparticle of a neutron?

• A. Antineutrino
• B. Positron
• C. Antiproton
• D. Electron

Correct answer: C

Rationale: The antiparticle of a neutron is an antineutron, which is composed of an antiproton and an antineutrino. The antineutrino (choice A) is not the antiparticle of a neutron. A positron (choice B) is the antiparticle of an electron, not a neutron. An electron (choice D) is a fundamental particle, not an antiparticle. Therefore, the correct answer is an antiproton (choice C), as it forms an antineutron when combined with an antineutrino.

2. What is the electrical charge of the nucleus?

• A. A nucleus always has a positive charge.
• B. A stable nucleus has a positive charge, but a radioactive nucleus may have no charge and instead be neutral.
• C. A nucleus always has no charge and is instead neutral.
• D. A stable nucleus has no charge and is instead neutral, but a radioactive nucleus may have a charge.

Correct answer: A

Rationale: A nucleus always has a positive charge. This is because the nucleus is composed of positively charged protons, along with neutral neutrons. The positive charge of the protons is balanced by the negative charge of the surrounding electrons in an atom, resulting in an overall neutral charge for the atom as a whole. Therefore, choice A is correct as it accurately reflects the positive charge of the nucleus due to the presence of protons. Choices B, C, and D are incorrect because they do not accurately represent the fundamental composition and charge distribution within an atom's nucleus. A stable nucleus consists of positively charged protons and neutral neutrons, leading to an overall positive charge, and not a neutral charge as suggested in the incorrect choices.

3. What phenomenon occurs when two identical waves are perfectly aligned and reinforce each other?

• A. Refraction
• B. Reflection
• C. Diffraction
• D. Constructive interference

Correct answer: D

Rationale: Constructive interference occurs when two identical waves are perfectly aligned and reinforce each other. This results in an increase in the overall amplitude of the wave. Refraction refers to the bending of waves as they pass from one medium to another, reflection is the bouncing back of waves when they encounter a boundary, and diffraction is the bending of waves around obstacles and openings. In this scenario, the waves are not changing direction or bending but rather combining to produce a wave with a larger amplitude, which is characteristic of constructive interference.

4. What is the momentum of a car with a mass of 1500 kg moving at a speed of 20 m/s?

• A. 30,000 kg m/s
• B. 1500 kg m/s
• C. 20 kg m/s
• D. Momentum cannot be determined without knowing the direction of motion.

Correct answer: A

Rationale: The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the momentum of the car can be determined using the formula momentum = mass x velocity. Substituting the given values, momentum = 1500 kg x 20 m/s = 30,000 kg m/s. Therefore, the correct answer is A, 30,000 kg m/s. Choice B (1500 kg m/s) is incorrect because that value represents the mass of the car, not its momentum. Choice C (20 kg m/s) is incorrect as it only represents the speed of the car, not its momentum. Choice D (Momentum cannot be determined without knowing the direction of motion) is incorrect because momentum is a vector quantity and can be determined using magnitude and direction, but in this case, only the magnitude is required.

5. The neutral theory of molecular evolution proposes that:

• A. Most mutations in DNA are selectively neutral and do not affect an organism's fitness.
• B. All mutations are beneficial and contribute to the adaptation of a population.
• C. The rate of evolution is primarily driven by strong directional selection pressures.
• D. Genetic drift plays a negligible role in shaping genetic variation within populations.

Correct answer: A

Rationale: Rationale: A) The neutral theory of molecular evolution, proposed by Motoo Kimura in the 1960s, suggests that the majority of mutations that occur in DNA are selectively neutral, meaning they do not have a significant impact on an organism's fitness. These neutral mutations are not subject to natural selection and are allowed to accumulate in populations over time. This theory helps explain the high levels of genetic variation observed within populations. B) Option B is incorrect because not all mutations are beneficial. Mutations can be neutral, harmful, or beneficial, and the neutral theory specifically focuses on the idea that many mutations are neutral in their effects. C) Option C is incorrect because the neutral theory suggests that evolution is not primarily driven by strong directional selection pressures. Instead, it emphasizes the role of genetic drift and the accumulation of neutral mutations in shaping genetic variation. D) Option D is incorrect because

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