Waves and the electromagnetic spectrum Flashcards
What is the equation for wave speed?
Wave speed (m/s) = frequency (Hz) x wavelength (m)
This equation describes how the speed of a wave is determined by its frequency and wavelength.
What is the formula to calculate frequency?
Frequency (Hz) = 1 / time period (s)
This formula indicates that frequency is the inverse of the time period.
What is a wave?
A means of transferring energy or information from one point to another without transferring matter between the two points.
Waves can carry energy and information effectively across distances.
Define transverse waves.
Waves where the direction of vibration is at 90° to the direction of movement.
Examples include light waves, which have crests and troughs.
What are the key characteristics of transverse waves?
Crests and troughs
Crests are the highest points, while troughs are the lowest points in a transverse wave.
Define longitudinal waves.
Waves where the vibrations of the particles are along the direction in which the wave travels.
Sound waves are a common example of longitudinal waves.
What are the key characteristics of longitudinal waves?
Compressions and rarefactions
Compressions are regions where particles are close together, while rarefactions are regions where they are stretched apart.
Fill in the blank: A wave is a means of transferring energy or information from one point to another without transferring _______.
matter
This highlights the fundamental property of waves.
What is amplitude in the context of waves?
The maximum displacement of the vibration from the undisturbed position.
Measured in metres.
Define frequency.
The number of waves or oscillations per second.
Measured in hertz (Hz).
What is wavelength?
The distance between a point on a wave and the same point on the next wave (e.g., from crest to crest).
Measured in metres.
What does the period of a wave refer to?
The time for one complete wave or oscillation.
Measured in seconds.
How is wave speed defined?
The speed at which the wave travels in its direction of motion.
Measured in metres per second (m/s).
What is a wave front?
The front of the wave, or the same point on each wave, typically the crest or peak of the wave.
Is light part of the electromagnetic spectrum?
Yes.
What is the speed of light in a vacuum?
3 x 10^8 m/s.
List three characteristics of waves in the electromagnetic spectrum.
- Travel at the same speed in a vacuum
- Transfer energy
- Can be reflected and refracted
True or False: All waves in the electromagnetic spectrum are transverse waves.
True.
Fill in the blank: The distance between points on a wave is measured in _______.
[metres]
Fill in the blank: The number of waves per second is known as _______.
[frequency]
Fill in the blank: The time taken for one complete wave is referred to as _______.
[period]
What is the order of the electromagnetic spectrum (in order of decreasing wavelength / increasing frequency)?
Radio waves
Microwaves
Infrared waves
Visible light (ROYGBIV)
Ultraviolet
X-rays
Gamma Rays
What section of the waves can our eyes detect?
Visible light
What is the order of the electromagnetic spectrum in decreasing wavelength / increasing frequency?
- Radio waves
- Microwaves
- Infrared
- Visible light
- Ultraviolet
- X-rays
- Gamma rays
What happens to frequency as wavelength increases?
Frequency decreases
What are the colors of visible light in order of decreasing wavelength / increasing frequency?
- Red
- Orange
- Yellow
- Green
- Blue
- Indigo
- Violet
What is a use of radio waves?
Broadcasting and communications
What is a common use for microwaves?
Cooking and satellite transmissions
Infrared is commonly used in __________.
Heaters and night vision equipment
What applications use visible light?
- Optical fibres
- Photography
What is ultraviolet light used for?
Fluorescent light e.g. torch
What medical applications utilize X-rays?
Observing internal structure of objects and materials
Gamma rays are used for __________.
Sterilising food and medical equipment
What can excessive exposure to higher frequency electromagnetic waves lead to?
Damaging cells, mutations, cancer
What is a potential effect of microwaves on the body?
Internal heating of body tissue
What damage can infrared radiation cause?
Skin burns
What are the potential effects of ultraviolet radiation?
Damage to surface cells, blindness, skin cancer
What health risk is associated with X-rays?
Cancer
Which type of radiation is considered the most dangerous?
Gamma rays
What are the protective measures against UV radiation?
Wear sunglasses, sun cream, stay in the shade
What should be worn for protection from gamma rays?
Lead clothing
What does ‘tera’ represent in the index of the electromagnetic spectrum?
T - 10^12
What does ‘giga’ represent in the index of the electromagnetic spectrum?
G - 10^9
What does ‘mega’ represent in the index of the electromagnetic spectrum?
M - 10^6
What does ‘kilo’ represent in the index of the electromagnetic spectrum?
k - 10^3
What does ‘milli’ represent in the index of the electromagnetic spectrum?
m - 10^-3
What does ‘micro’ represent in the index of the electromagnetic spectrum?
μ - 10^-6
What does ‘nano’ represent in the index of the electromagnetic spectrum?
n - 10^-9
What does ‘pico’ represent in the index of the electromagnetic spectrum?
p - 10^-12
What does ‘femto’ represent in the index of the electromagnetic spectrum?
f - 10^-15
