3.1 Waves Flashcards
How are waves generated?
By causing particles to move/vibrate.
What does a wave do?
Transfers energy.
What is a transverse wave in relation to the direction of travel of the wave and the direction of movement of particles?
the direction of travel of the wave is perpendicular to the direction of movement of particles.
What is a longitudinal wave in relation to the direction of travel of the wave and the direction of movement of particles?
the direction of travel of the wave is parallel to the direction of movement of particles.
Can transverse waves travel through a vacuum?
yes
Can longitudinal waves travel through a vacuum?
no
Give examples of longitudinal waves…
sound
Give examples of transverse waves…
- infrared
- visible light
- ultraviolet
- TV
- radio
- microwaves
What is the crest of a wave?(2)
- point of maximum displacement
- highest point of a wave
What is the trough of a wave? (2)
- point of minimum displacement
- lowest point of a wave
What is the amplitude of a wave? (2)
What is the symbol and unit?
- vertical distance from the zero line to either the crest or the trough
- gives a measure of the quantity of energy wave possesses
- A
- metres (m)
what is the wavelength of the wave? (2)
What is the symbol and unit?
- length of one complete wave
- horizontal distance between the same point on consecutive waves
- landa
- metres (m)
What is the frequency? What is the unit and symbol?
- number of waves that pass a point in one second
- f
- hertz (Hz)
What is the time period? What is the unit and symbol?
- time taken for one complete wave to pass a point
- T
- seconds (s)
What is the equation linking number of waves, frequency and time?
N=ft
number of waves=frequency times time
What is the equation linking frequency and time period?
f=1/T
T=1/f
What is the equation linking speed, frequency and wavelength?
v=f(landa)
speed equals frequency times wavelength
What three things link the members of the electromagnetic spectrum?
- all transverse
- all travel through vacuums
- all travel at 3x10^8 m/s
Give the members of the electromagnetic spectrum in order of wavelength shortest to longest…
Gamma Rays, x-rays, ultraviolet, visible light, infrared, microwaves, television, radio
Give the colours in order of wavelength shortest to longest that make up visible light…
violet, indigo, blue, green, yellow, orange, red
Give the members of the electromagnetic spectrum in order of frequency low to high…
radio, television, microwaves, infrared, visible light, ultraviolet, x-ray, gamma rays.
Describe a setup to measure the speed of sound in air…
1) place two microphones 1m apart both connected to an electrical timer
2) use a pin to pop a balloon.
3) timer starts when first microphone detects sound wave
4) timer stops when second microphone detects sound wave
5) speed of sound calculated using v=d/t
6) repeat and use an average
What is the speed of sound in air?
340m/s
