Free Practice Questions for WGU Integrated-Physical-Sciences Exam

Locations in the southern hemisphere receive the most direct sunlight when the southern hemisphere is tilted towards the sun.

In the diagram, position D represents this orientation, where the southern hemisphere is experiencing summer and receiving direct sunlight. References:

Integrated Physical Sciences resources on seasonal changes and Earth's tilt.

An observational study involves collecting data without manipulating any variables. The question "What is the brightest star that can be seen from Earth?" fits this criteria as it involves observing and recording data about stars without any experimental intervention. Other options involve controlled experiments where variables are manipulated. References:

Integrated Physical Sciences, Chapter 2: Methods of Scientific Investigation

Definition of Substance Types:

Element (A): A pure substance consisting of only one type of atom.

Compound (B): A substance formed when two or more elements are chemically bonded.

Isotope (C): Atoms of the same element with different numbers of neutrons.

Mixture (D): A combination of two or more substances that are not chemically bonded.

Composition of Sand: Sand is composed of various small rock and mineral particles, which are physically combined but not chemically bonded.

Conclusion: Sand is a mixture.

References:

Properties of Mixtures: Characteristics and examples of mixtures in physical science.

**Identify the contradiction:** NASA scientists found chemical compounds in a Martian meteor that suggested the possibility of ancient life on Mars. However, similar compounds were also found in Moon rocks, where life is not believed to have existed. - **Analyze the evidence:** The presence of these compounds on both Mars and the Moon suggests that these compounds are not unique indicators of life. - **Scientific approach:** To resolve the contradiction, scientists must consider the broader context and properties of these compounds. The appropriate response is to recognize that the compounds alone do not provide conclusive evidence of life. This requires a cautious interpretation of the findings and a search for additional, more definitive indicators of life. - **Conclusion:** The correct approach is to understand that these chemical compounds do not necessarily indicate life, as their presence can be attributed to non-biological processes as well. **References:** Integrated Physical Sciences textbooks, scientific journals on astrobiology, and NASA reports on Martian and lunar geology.

Gravity is the force responsible for the motion of a ball falling from a shelf to the floor. As the ball is released, gravity pulls it downward, causing it to accelerate towards the floor. References:

Integrated Physical Sciences, Chapter 3: Forces and Motion

When heavy rain occurs, the water that does not infiltrate into the ground or evaporate runs off over the land surface. This runoff water collects in rivers, lakes, and streams, becoming part of the surface water reservoir. Surface water is the body of water above ground, including rivers, lakes, reservoirs, and oceans, which is replenished by precipitation and runoff.

References:

Integrated Physical Sciences documents on the water cycle and hydrology.

Textbook resources on water reservoirs and the distribution of Earth's water.

*Understand the claim:** In 2011, scientists observed neutrinos that appeared to travel faster than light, which would contradict Einstein’s theory of special relativity. - **Scientific principles:** Einstein’s theory of special relativity has been extensively validated and is a cornerstone of modern physics. Any claim that contradicts it requires thorough investigation. - **Appropriate response:** The scientific method dictates that extraordinary claims require extraordinary evidence. The first step should be to check the experimental setup for errors or anomalies that could explain the unexpected results. - **Replication:** Independent replication of the experiment is essential to confirm or refute the findings. If other scientists can replicate the results under controlled conditions, the claim gains credibility. Otherwise, the initial results are likely due to experimental errors. - **Conclusion:** The best approach is to critically evaluate the experiment and attempt to replicate the results, ensuring the integrity of the scientific process. **References:** Peer-reviewed journals on particle physics, reports from CERN, and documentation on the principles of the scientific method.

As comets approach the Sun, the increased solar radiation causes the ice within the comet to evaporate (a process called sublimation), releasing gas and dust particles. This creates a visible atmosphere called a coma, and the solar wind then blows this material away from the comet, forming a tail. The tail always points away from the Sun due to the force of the solar wind. References:

NASA’s Comet Exploration Missions

"Cometary Physics" - European Space Agency Publications

Energy is released during phase changes from gas to liquid (condensation). When water vapor in a cloud condenses to form raindrops, it releases energy to the surroundings. This is because the gas phase (water vapor) has higher energy than the liquid phase (raindrops), and the transition to a lower energy state (liquid) releases the excess energy.

References:

Integrated Physical Sciences materials on condensation and energy release.

Concepts of energy changes during phase transitions.

The early universe consisted primarily of hydrogen atoms, which began to coalesce due to gravitational attraction.

As these hydrogen atoms collected into large clouds, the gravitational force continued to draw them closer together, increasing pressure and temperature at the core.

Once the pressure and temperature were high enough, nuclear fusion ignited, forming the first stars.

This process was driven by the gravitational force, not by other forces like magnetic or momentum from the big bang. References:

Integrated Physical Sciences materials on the formation of stars and gravitational forces.