praxis elementary science 5005 practice test

A series of tests developed by ETS to assess the skills and knowledge of prospective teachers.

The pitch of a sound is related to which of the following properties of a sound wave?
  • A. Speed
  • B. Frequency
  • C. Amplitude
  • D. Energy
Correct Answer & Rationale
Correct Answer: B

The pitch of a sound is directly related to its frequency, which refers to how many sound wave cycles occur in one second. Higher frequencies produce higher pitches, while lower frequencies result in lower pitches. Option A, speed, refers to how fast sound travels through a medium but does not affect pitch. Option C, amplitude, relates to the loudness or intensity of a sound rather than its pitch. Option D, energy, is associated with the overall power of the sound wave but does not determine pitch. Thus, frequency is the key property that defines the pitch of a sound.

Other Related Questions

Which TWO of the following statements about the universe are true?
  • A. The universe is expanding.
  • B. The Milky Way galaxy contains most of the stars in the universe.
  • C. A star's size, temperature, and composition typically remain constant throughout its life cycle.
  • D. A black hole is usually detected by the intense visible light it emits.
Correct Answer & Rationale
Correct Answer: A

Option A accurately reflects current astronomical understanding, as evidence shows the universe is expanding due to the redshift of distant galaxies. Option B is incorrect; while the Milky Way is large, it contains only a small fraction of the universe's stars, which are spread across billions of galaxies. Option C is misleading; stars undergo significant changes in size, temperature, and composition throughout their life cycles, particularly during phases like red giant or supernova. Option D is also false; black holes do not emit visible light; they are detected through their gravitational effects and the radiation from material falling into them.
Which of the following best describes a comet?
  • A. A small planet orbiting the Sun between Mars and Jupiter.
  • B. A chunk composed primarily of metal that enters Earth's atmosphere.
  • C. A chunk composed primarily of rock, ice, and dust orbiting the Sun in an elliptical path.
  • D. A dark region that appears periodically on the surface of the Sun.
Correct Answer & Rationale
Correct Answer: C

Option C accurately describes a comet as a chunk composed primarily of rock, ice, and dust that orbits the Sun in an elliptical path. This definition captures the essential components and behavior of comets. Option A incorrectly defines a comet as a small planet, which is misleading; comets are distinct from asteroids and do not have the same characteristics. Option B describes a meteoroid, which is a metallic chunk entering Earth's atmosphere, not a comet. Option D refers to sunspots, which are dark regions on the Sun's surface, unrelated to comets. Each incorrect option misrepresents the nature of comets, highlighting the unique characteristics of these celestial bodies.
A student is conducting an experiment to determine how the temperature of water affects the rate at which sugar dissolves. The student uses four beakers with the same amount of water at different temperatures: 20C, 40C, 60C, and 80C. The student adds the same amount of sugar to each beaker and stirs for the same length of time. Which of the following is the independent variable in this experiment?
  • A. The amount of sugar added to each beaker.
  • B. The temperature of the water in each beaker.
  • C. The time it takes for the sugar to dissolve.
  • D. The amount of stirring done in each beaker.
Correct Answer & Rationale
Correct Answer: B

In this experiment, the temperature of the water in each beaker is the independent variable, as it is the factor that the student deliberately changes to observe its effect on sugar dissolution. Option A, the amount of sugar, remains constant across all beakers, making it a controlled variable rather than an independent one. Option C, the time taken for sugar to dissolve, is the dependent variable, as it is measured to assess the impact of the temperature. Option D, the amount of stirring, is also controlled to ensure consistency in the experiment. Thus, only the temperature is varied to determine its influence on the rate of dissolution.
Which of the following is true about the nucleus of an atom?
  • A. The nucleus has a negative charge.
  • B. The nucleus is neutral with no charge.
  • C. The electrons and protons are located in the nucleus.
  • D. The neutrons and protons are located in the nucleus.
Correct Answer & Rationale
Correct Answer: D

The nucleus of an atom is composed of protons and neutrons, making option D accurate. Protons carry a positive charge, while neutrons are neutral, contributing to the overall positive charge of the nucleus. Option A is incorrect because the nucleus does not have a negative charge; it is positively charged due to protons. Option B is also wrong, as the nucleus is not neutral; it has a positive charge from the protons. Lastly, option C is misleading because electrons are located outside the nucleus in electron shells, not within it.