☢️ • Lesson 3.5 : The Electromagnetic Spectrum and Sound (Phys) Flashcards
After this lesson, you will have mastered the electromagnetic spectrum, as well as the production of sound, vibrations, frequencies, and the simple phenomena of magnetism.
What are the 7 colours of the visible spectrum in order of frequency?
Frequency Order: Violet, Indigo, Blue, Green, Yellow, Orange, Red
What are the 7 colours of the visible spectrum in order of wavelength?
Wavelength Order: Red, Orange, Yellow, Green, Blue, Indigo, Violet
What are the main regions of the electromagnetic spectrum in order of frequency?
Frequency Order: Gamma rays, X-rays, Ultraviolet, Visible light, Infrared, Microwaves, Radio waves
What are the main regions of the electromagnetic spectrum in order of wavelength?
Wavelength Order: Radio waves, Microwaves, Infrared, Visible light, Ultraviolet, X-rays, Gamma rays
How fast do all electromagnetic waves travel in a vacuum?
3.0 × 10^8 m/s,
which is approximately the same in air.
What are some applications of radio waves of the electromagnetic spectrum?
Radio, TV transmissions, radar
What are some applications of microwaves of the electromagnetic spectrum?
Satellite TV, mobile phones, microwave ovens
What are some applications of infrared of the electromagnetic spectrum?
Remote controllers, thermal imaging
What are some applications of visible light of the electromagnetic spectrum?
Vision, photography
What are some applications of ultraviolet of the electromagnetic spectrum?
Detecting fake bank notes
What are some applications of x-rays of the electromagnetic spectrum?
Medical scanning, security scanners
What are some applications of gamma rays of the electromagnetic spectrum?
Cancer detection and treatment
What are the harmful effects of excessive exposure to ultraviolet radiation?
Skin damage, skin cancer, eye conditions
What are the harmful effects of excessive exposure to x-rays and gamma rays radiation?
Cell mutations or damage leading to cancer
How is sound produced by vibrating sources?
Sound is produced when a source vibrates, creating pressure waves in the surrounding medium (usually air), which we perceive as sound.
What is the longitudinal nature of sound waves in air?
Sound waves are longitudinal, with particles moving back and forth in the same direction as the wave, creating compressions and rarefactions.
What are compressions and rarefactions in sound waves?
Compressions are regions of high pressure where particles are close together, and rarefactions are regions of low pressure where particles are spread apart.
What is the audible frequency range for humans?
Humans can hear frequencies between 20 Hz and 20 kHz.
What is needed to transmit sound waves?
A medium, such as air, water, or solids, is needed to transmit sound waves.
How do you measure the speed of sound in air?
By measuring the distance a sound wave travels and the time it takes, then using the formula: speed = distance/time.
How does sound speed vary in different mediums?
Sound travels faster in solids than in liquids and faster in liquids than in gases.
How do amplitude and frequency affect sound?
Amplitude affects loudness; higher amplitude = louder sound.
Frequency affects pitch; higher frequency = higher pitch.
What is an echo?
An echo is the reflection of a sound wave off a surface.
What is ultrasound?
Ultrasound is sound with a frequency higher than 20kHz.
