WCAS Waves and Their Applications 1 — Questions and Answers
Question 1: What property of a wave is defined as the number of complete wave cycles that pass a given point per second?
- Amplitude
- Frequency (Correct answer)
- Wavelength
- Period
Correct answer: Frequency
Frequency is the number of complete wave cycles passing a point per second, measured in hertz (Hz).
Question 2: Which of the following types of waves requires a medium to travel through?
- Radio waves
- Light waves
- Sound waves (Correct answer)
- Ultraviolet rays
Correct answer: Sound waves
Sound is a mechanical wave and must travel through a physical medium such as air, water, or a solid.
Question 3: If a wave's frequency increases while its speed stays constant, what happens to its wavelength?
- It increases
- It decreases (Correct answer)
- It stays the same
- It doubles
Correct answer: It decreases
Since wave speed = frequency × wavelength, if frequency increases and speed is constant, wavelength must decrease.
Question 4: The amplitude of a wave is best described as:
- The distance between two consecutive crests
- The number of waves produced per second
- The maximum displacement of a medium from its rest position (Correct answer)
- The speed at which the wave travels
Correct answer: The maximum displacement of a medium from its rest position
Amplitude measures how far the wave displaces the medium from its equilibrium position, which relates to the wave's energy.
Question 5: Which of the following is an example of a transverse wave?
- Sound wave traveling through air
- Compression wave on a spring
- Light wave traveling through space (Correct answer)
- Seismic P-wave during an earthquake
Correct answer: Light wave traveling through space
Light waves are electromagnetic transverse waves in which oscillations are perpendicular to the direction of energy travel.
Question 6: When a wave passes from one medium into another, which wave property always remains unchanged?
- Speed
- Wavelength
- Frequency (Correct answer)
- Amplitude
Correct answer: Frequency
Frequency is determined by the source of the wave and does not change when the wave enters a new medium.
Question 7: Which equation correctly describes the relationship between wave speed (v), frequency (f), and wavelength (λ)?
- v = f × λ (Correct answer)
- v = f / λ
- v = λ / f
- v = f + λ
Correct answer: v = f × λ
The wave equation states that wave speed equals frequency multiplied by wavelength (v = fλ).
WCAS Waves and Their Applications 1
What property of a wave is defined as the number of complete wave cycles that pass a given point per second?