WCAS Cheat Sheet 2026

The 30 highest-yield WCAS facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. According to the law of reflection, when a light ray bounces off a flat mirror, the angle of incidence equals: → The angle of reflection
2. Which of the following is an example of a chemical change? → A bicycle frame rusting over time.
3. A student observes several phenomena in a lab. Which of the following observations most strongly indicates that a chemical reaction has occurred? → The temperature of a mixture decreases as two liquids are combined.
4. What type of rock is formed from the cooling and solidification of magma or lava? → Igneous
5. Which term describes the characteristics that help organisms survive or reproduce in their environment? → Adaptation
6. Which statement accurately describes the relationship between genes, chromosomes, and DNA? → Genes are segments of DNA, which is tightly coiled to form chromosomes.
7. What type of weathering involves the physical breakdown of rocks into smaller pieces without changing their chemical composition? → Mechanical weathering
8. Which of the following is NOT a type of plate boundary? → Perpendicular boundary
9. What term describes an inherited behavior that an organism can perform without ever learning how to do it? → Instinct
10. A model of a water molecule (H₂O) is shown to a student. Which statement accurately describes the atomic composition of this molecule? → It is composed of two hydrogen atoms and one oxygen atom.
11. Which term describes a behavior that is learned through practice? → Habit
12. Which of the following is the best definition of a biological adaptation? → A heritable trait that increases an organism's fitness in its specific environment.
13. Which of the following statements BEST describes the primary role of genetic mutation in the process of evolution? → Mutations are the ultimate source of new genetic variation in a population.
14. How does increasing the frequency of electromagnetic radiation affect the energy carried by each photon? → Energy increases as frequency increases
15. What property of a wave is defined as the number of complete wave cycles that pass a given point per second? → Frequency
16. Which term describes the variable in an experiment that is intentionally changed or manipulated? → Manipulated variable
17. Which of the following describes a density-independent limiting factor that could affect a population of deer in a forest? → A sudden, severe forest fire that burns a large area.
18. Which equation correctly describes the relationship between wave speed (v), frequency (f), and wavelength (λ)? → v = f × λ
19. Which of the following is the primary source of energy that drives the Earth's water cycle, causing evaporation and transpiration? → Solar radiation from the Sun
20. What term describes the factors that are kept constant in an experiment each time it is tested? → Controlled variables
21. Which of the following types of waves requires a medium to travel through? → Sound waves
22. Which wave behavior allows waves to bend around the edges of obstacles or openings? → Diffraction
23. Which term describes the physical or behavioral traits that develop during an organism's life in response to environmental factors? → Acquired characteristic
24. An incandescent light bulb is switched on. It produces light and also becomes very hot. This scenario is an example of energy being transformed from: → Electrical energy into light and thermal energy.
25. According to the law of conservation of energy, which of the following statements is true? → The total amount of energy in an isolated system remains constant over time.
26. What type of eclipse occurs when the Moon passes directly between the Earth and the Sun? → Solar eclipse
27. Which of the following best defines a 'trade-off' in the context of engineering design? → A design choice where improving one desired feature necessitates worsening another.
28. When a wave passes from one medium into another, which wave property always remains unchanged? → Frequency
29. What term describes the physical or behavioral traits that are programmed into an organism's DNA and are passed down from parent to offspring? → Inherited characteristic
30. Mitochondria are often called the 'powerhouses' of the cell. What is the primary function of mitochondria in both plant and animal cells? → To break down sugars to release energy in the form of ATP.