Unit 9: Waves

What is a crest?

The highest point of a wave.

What is a trough?

The lowest point of a wave.

What is amplitude?

The maximum displacement of points on a wave from its rest position.

What is wavelength?

The distance between successive crests or troughs of a wave.

What are rarefactions?

Regions in a longitudinal wave where particles are spread apart.

What are compressions?

Regions in a longitudinal wave where particles are close together.

How many waves are shown in a diagram?

Count the number of complete wave cycles present in the diagram.

What is the difference between transverse and longitudinal waves?

Transverse waves oscillate perpendicular to the direction of wave travel, while longitudinal waves oscillate parallel to the direction of wave travel.

Give examples of transverse waves.

Examples include light waves and waves on a string.

Give examples of longitudinal waves.

Examples include sound waves and seismic P-waves.

What is the difference between mechanical and electromagnetic waves?

Mechanical waves require a medium to travel through, while electromagnetic waves can travel through a vacuum.

What is the electromagnetic spectrum?

A range of all types of electromagnetic radiation organized by wavelength, frequency, and energy.

What is the wave equation?

The equation that relates wave speed (v), wavelength (λ), and frequency (f): v = f × λ.

What is frequency?

The number of waves that pass a point in one second, measured in Hertz (Hz).

What is period?

The time it takes for one complete wave cycle to pass a point, measured in seconds.

What is reflection?

The bouncing back of a wave when it hits a barrier.

What is refraction?

The bending of a wave as it passes from one medium to another due to a change in speed.

What is diffraction?

The spreading of waves around obstacles or through openings.

What is resonance?

The phenomenon where a system oscillates with greater amplitude at specific frequencies.

What is interference?

The interaction between two or more waves that combine to form a new wave pattern.

What is wave-particle duality?

The principle that light and other forms of electromagnetic radiation exhibit both wave-like and particle-like properties.

What is the photoelectric effect?

The emission of electrons from a material when it absorbs light or electromagnetic radiation.

What is a photon?

A particle of light that carries energy and has no mass.

How do technological devices use wave behavior?

Devices like radios and cell phones use wave principles to transmit and capture information and energy.

What happens when waves overlap?

They can interfere constructively (amplitudes add) or destructively (amplitudes subtract) depending on their phases.

What is the relationship between wave speed, wavelength, and frequency?

Wave speed is the product of wavelength and frequency (v = f × λ).

What occurs when the amplitude of waves increases?

The energy carried by the waves increases, potentially affecting the motion of objects in the wave.

Why do astronauts use radio headsets in space?

Astronauts use radio headsets because electromagnetic waves can travel in a vacuum.

What is an example of a longitudinal wave?

A sound wave is an example of a longitudinal wave.

What type of wave is shown in a coiled spring diagram?

The wave shown in the diagram is a longitudinal wave.

What characteristic must differ between a 500 Hz and a 400 Hz sound wave?

The wavelength must differ between the two waves.

How does ultraviolet (UV) light compare to visible light?

UV light has a higher frequency than visible light.

Which wave has the longest period based on frequency?

Wave Y has the longest period because it has the lowest frequency of 264 Hz.

What angle is formed by the reflected ray of light and the normal line when the incident angle is 30°?

The angle formed by the reflected ray and the normal line is also 30°.

Why do people see light before hearing sound at a race?

Mechanical waves travel at a slower speed than electromagnetic waves.

What conclusion can be drawn about sound speed in different states?

Sound generally travels at a faster speed in solid substances than in liquid substances.

What is reflection in wave properties?

Reflection is when waves bounce off a surface.

What is refraction in wave properties?

Refraction is when waves change direction as they travel at different speeds in different media.

What is diffraction in wave properties?

Diffraction is when waves can travel around obstacles and openings.

What is resonance in wave properties?

Resonance occurs when the natural frequency of an object is matched, amplifying its vibrations.

What happens in the photoelectric effect regarding frequency?

A minimum frequency is required to eject electrons; intensity alone does not matter.

What is the relationship between frequency and energy of photons?

Photons with higher frequencies have higher energy.

How to calculate the wavelength of radio waves at 94.5 MHz?

Use the formula: wavelength = speed of light / frequency.

How fast is sound in a swimming pool if it takes 0.033 seconds to travel 50 meters?

The speed of sound is approximately 1515 m/s, which is faster than in air.

What is the frequency of sound with a wavelength of 3.44 m?

The frequency can be calculated using the formula: frequency = speed / wavelength.

How does the speed of light change in water?

In water, light slows down to 75% of its speed in a vacuum.

Which laser light has the largest frequency?

The blue laser light has the largest frequency.

Which laser light has the longest wavelength?

The red laser light has the longest wavelength.

Which laser light has the fastest speed?

All laser lights travel at the same speed in a vacuum.

How to calculate the frequency of red laser light with a wavelength of 700 nm?

Use the formula: frequency = speed of light / wavelength.

How to calculate the wavelength of green laser light with a frequency of 5.6 x 10^14 Hz?

Use the formula: wavelength = speed of light / frequency.

How to calculate the speed of a wave with a wavelength of 1.5 m and a period of 1.333 seconds?

Use the formula: speed = wavelength / period.