Waves Flashcards
Wave meaning
a periodic disturbance travelling through space, characterised by a vibrating medium
Progressive wave meaning
a wave that carries energy from one place to another
Displacement meaning
the distance of a point on the wave from its undisturbed or equilibrium position
Amplitude meaning
the maximum displacement of a wave
Wavelength meaning
the distance between 2 adjacent points on a wave oscillating in step with eachother
Period meaning
the time taken for one complete oscillation of a point in a wave
Frequency meaning
the number of oscillations per unit time of a point in a wave
Longitudinal wave meaning
a wave in which the particles of the medium oscillate along in the direction in which the wave travels
Transverse wave meaning
a wave in which the particles of the medium oscillate at right angles to the direction in which the wave travels
Compression meaning
the point in a sound wave at which the air pressure is at maximum
Rarefaction meaning
a region in a sound wave where the air pressure is less than its mean value
Phase difference meaning
the fraction of a cycle between 2 oscillating particles, expressed in either degrees or radians
Phase difference calculation
∆Φ = [x / λ] * 180º or 2π
Intensity formula
intensity = power / area
Intensity equation
Intensity ∝ amplitude²
Intensity meaning
intensity is the rate of energy transmitted (power) per unit area at right angles to the wave velocity
Wave speed formula
v = λf
v is speed in m/s
λ is wavelength in m
f is frequency in Hz
Doppler effect meaning
the change in frequency or wavelength of a wave observed when the source of the wave observed when the source of the wave is moving towards or away from the observer (or the observer is moving relative to the source)
Doppler effect formula
f’ = f(V𝓌 / V𝓌 ± Vₛ)
Electromagnetic spectrum meaning
the family of waves that travel through a vacuum at a speed of 3.00 x 10⁸ ms⁻¹
Magnetic field meaning
a force field in which a magnet, a wire carrying current or a moving charge experiences a force
Electromagnetic wave meaning
a transverse wave travelling through space as vibrations of electric and magnetic fields
Wavelength ranges of em waves
radio 10⁴ micro 10⁻² infrared 10⁻⁶ visible** ultraviolet 4 x 10⁻⁸ x-ray 10⁻¹² gamma-ray 10⁻¹⁶
- red 7 x 10⁻⁷
- violet 4 x 10⁻⁷
Electric field meaning
a force a field in which an electric charged particle experiences a force
Plane polarised meaning
describes a transverse wave with oscillation in just one plane, only transverse waves can be polarised
Malus’ Law formula
I = I₀cos²θ