CIE IGCSE Physics (0625) - Waves Flashcards
(25 cards)
What do waves transfer?
Waves transfer energy without transferring matter
What is a mechanical wave?
A wave that requires a medium (like air, water, or solid) to travel through
What is a wavefront?
A line joining adjacent points on a wave that are all in step with each other (e.g. the crests of waves in a ripple tank)
Define frequency | define the word and write down the unit they are measured in
The number of waves per second measured in hertz (hz) or per second (1/s)
Define wavelength
The distance between two adjacent identical points of a wave
Define amplitude
The maximum displacement caused by a wave
Describe the motion of particles in a transverse wave
Particles vibrate perpendicular to the direction of energy transfer
Describe the motion of particles in a longitudinal wave
Particles vibrate parallel to the direction of energy transfer
Recall the wave speed (v) equation
Wave speed (v) = frequency (f) x wavelength (λ)
Describe the law of reflection
The angle of incidence (i) = the angle of reflection (r)
What is refraction?
The bending of light as it passes from one medium to another due to a change in speed, occurring when the light enters the new medium at an angle
What is diffraction?
The spreading of waves when it travels through a gap or past the edge of an object
What happens to a light ray as it passes from air into glass?
It slows down, bends towards the normal, and its wavelength decreases
How is the refractive index (n) defined using the speed of light in a vacuum or air (c) and in a material (v)?
Refractive index (n) = speed of light in vacuum (c) / speed of light in material (v)
What is the formula for refractive index (n) using angles of incidence (i) and refraction (r)?
n = sin i / sin r
What is the formula linking refractive index (n) and critical angle (c)?
n = 1 / sin c
What is the cause of sound?
Sound is caused by vibrating objects
What type of wave is sound?
Longitudinal
What are the two key features of a longitudinal wave?
Compressions and rarefactions
What is the range of human hearing?
20-20,000 Hertz
What is needed to transmit sound waves?
A medium (e.g. air particles)
In which type of medium does sound travel the fastest—solid, liquid, or gas—and why?
Sound travels fastest in solids because their particles are packed closely together, allowing vibrations to pass through more quickly
Describe a sound with a high amplitude and low frequency
Loud and low pitch
Describe a sound with a low amplitude and high frequency
Quiet and high pitch
