Nokea
What element has the atomic number 17?
- A. Chlorine (Cl)
- B. Nitrogen (N)
- C. Sodium (Na)
- D. Fluorine (F)
Correct Answer: A
Rationale: The correct answer is Chlorine (Cl). The atomic number of an element corresponds to the number of protons in its nucleus. Chlorine has an atomic number of 17, indicating it has 17 protons. Therefore, the element with atomic number 17 is Chlorine (Cl). Choice B, Nitrogen (N), has an atomic number of 7, Choice C, Sodium (Na), has an atomic number of 11, and Choice D, Fluorine (F), has an atomic number of 9. These elements do not match the atomic number 17, making them incorrect choices.
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Why does a prism separate white light into its constituent spectral components?
- A. It absorbs certain colors
- B. Different colors experience varying speeds within the prism
- C. It bends all colors with the same magnitude
- D. It reflects specific colors
Correct Answer: B
Rationale: A prism separates white light into its constituent spectral components because different colors experience varying speeds within the prism due to their different wavelengths. This causes the light to refract at different angles, resulting in the separation of colors. When light enters the prism, it undergoes dispersion, where different colors are refracted at different angles due to their unique wavelengths. This phenomenon is known as chromatic dispersion. Choice A is incorrect because a prism does not absorb colors but refracts and disperses them. Choice C is incorrect because a prism refracts different colors at different angles, not with the same magnitude. Choice D is incorrect because a prism does not reflect colors but refracts and disperses them based on their wavelengths.
What property of a wave determines its pitch in sound waves?
- A. Amplitude
- B. Frequency
- C. Wavelength
- D. Speed
Correct Answer: B
Rationale: The pitch of a sound wave is determined by its frequency. Frequency is the number of cycles of a wave that occur in a unit of time, usually measured in hertz (Hz). Higher frequencies correspond to higher pitches, while lower frequencies correspond to lower pitches. Amplitude refers to the height of a wave and is related to the loudness of the sound. Wavelength is the distance between two consecutive points in a wave that are in phase, and speed is the rate at which a wave travels through a medium. Therefore, the correct answer is frequency as it directly correlates with the pitch of a sound wave.
What is the primary function of the lymphatic system?
- A. Transporting nutrients throughout the body
- B. Removing excess fluids and waste products from tissues
- C. Producing red blood cells
- D. Regulating body temperature
Correct Answer: B
Rationale: The primary function of the lymphatic system is to remove excess fluids, waste products, and toxins from tissues. It maintains fluid balance and supports the immune system by transporting lymph, which contains white blood cells, throughout the body. Choice A is incorrect as nutrient transport is primarily handled by the circulatory system. Choice C is incorrect because red blood cells are produced in the bone marrow, not the lymphatic system. Choice D is incorrect as the regulation of body temperature is mainly controlled by the endocrine system and thermoregulatory mechanisms in the body. Therefore, the correct answer is B.
What is the process by which a large, unstable nucleus splits into two smaller nuclei, releasing neutrons and energy?
- A. Alpha decay
- B. Beta decay
- C. Gamma decay
- D. Nuclear fission
Correct Answer: D
Rationale: Nuclear fission is the correct answer. It is the process in which a large, unstable nucleus splits into two smaller nuclei, releasing neutrons and energy. Alpha decay, beta decay, and gamma decay involve the emission of alpha particles, beta particles, and gamma rays, respectively. These decay processes do not result in the splitting of a nucleus like nuclear fission does.
What defines the period of a wave?
- A. The time it takes for one complete wave cycle to pass a point
- B. The distance between two adjacent crests or troughs
- C. The number of waves passing a point per unit time
- D. The maximum displacement of particles in a medium due to the wave
Correct Answer: A
Rationale: The period of a wave is defined as the time it takes for one complete wave cycle to pass a point. It is a crucial parameter in wave analysis and is typically measured in seconds. The period is directly related to the frequency of the wave, as they are reciprocals of each other. Therefore, the correct answer is the time it takes for one complete wave cycle to pass a point (choice A). The period is not related to the number of waves passing a point per unit time (choice C), the distance between two adjacent crests or troughs (choice B), or the maximum displacement of particles in a medium due to the wave (choice D).