praxis elementary science 5005 practice test

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

The rotation of Earth around its axis is responsible for which of the following?
  • A. The force of gravity
  • B. The day and night cycle
  • C. The temperature differences between seasons
  • D. The movement of continents relative to one another
Correct Answer & Rationale
Correct Answer: B

The rotation of Earth around its axis creates the day and night cycle, as different parts of the planet face the Sun and then move into its shadow. This explains why we experience daytime and nighttime in a 24-hour period. Option A is incorrect; gravity is primarily caused by Earth's mass, not its rotation. Option C is also wrong; temperature differences between seasons are due to Earth's tilt and its orbit around the Sun, not its rotation. Lastly, option D misrepresents the concept; the movement of continents is influenced by tectonic activity, not the rotation of Earth.

Other Related Questions

Which of the following is a statement that proposes a possible explanation for a phenomenon and can be tested through experimentation?
  • A. An observation
  • B. A variable
  • C. An experiment
  • D. A hypothesis
Correct Answer & Rationale
Correct Answer: D

A hypothesis is a statement that proposes a possible explanation for a phenomenon and can be tested through experimentation. It serves as a foundation for scientific inquiry. Option A, an observation, refers to data gathered through the senses and does not propose an explanation. Option B, a variable, is a factor that can change in an experiment but does not itself explain phenomena. Option C, an experiment, is a method used to test a hypothesis but is not a statement proposing an explanation. Thus, only a hypothesis encapsulates a testable explanation.
Recycling will best benefit the environment by minimizing which THREE of the following?
  • A. The consumption of raw materials
  • B. The incineration of materials in combustion for energy
  • C. The amount of materials in landfills
  • D. The reuse of materials in new products
Correct Answer & Rationale
Correct Answer: A,B,C

Recycling effectively minimizes the consumption of raw materials (A) by reusing existing materials, reducing the need for new resource extraction. It also decreases the amount of materials sent to landfills (C), which helps mitigate environmental issues associated with waste accumulation. Additionally, recycling reduces the incineration of materials for energy (B), lowering greenhouse gas emissions and air pollution. Option D, the reuse of materials in new products, is not minimized by recycling; rather, recycling facilitates this process. Therefore, A, B, and C are the primary benefits of recycling for environmental protection.
Of the following gases, which is found in the atmosphere in the greatest concentration?
  • A. O2
  • B. N2
  • C. H2
  • D. CO2
Correct Answer & Rationale
Correct Answer: B

Nitrogen (N2) constitutes about 78% of the Earth's atmosphere, making it the most abundant gas. Oxygen (O2), while essential for life, is present at around 21%, significantly less than nitrogen. Hydrogen (H2) is found in trace amounts and is not a major component of the atmosphere. Carbon dioxide (CO2) is also present in much smaller concentrations, approximately 0.04%, and is primarily significant for its role in climate regulation. Therefore, nitrogen is the predominant gas, while the others are present in much lower concentrations.
The speed of light in empty space, that is, a vacuum, is 300,000 km/s. The speed of sound in empty space is:
  • B. greater than 0 but less than 300,000 km/s
  • C. 300,000 km/s
  • D. greater than 300,000 km/s
Correct Answer & Rationale
Correct Answer: A

The speed of sound requires a medium, such as air or water, to propagate; it cannot travel through a vacuum. Therefore, the speed of sound in empty space is effectively zero. Option B suggests that the speed of sound is greater than 0 but less than 300,000 km/s, which is incorrect because sound cannot exist in a vacuum. Option C states it is 300,000 km/s, which misrepresents sound's nature, as this speed is specific to light. Option D claims it is greater than 300,000 km/s, which is impossible since sound cannot travel in a vacuum at all. Thus, the only valid conclusion is that the speed of sound in empty space is zero.