Oscillations and waves Flashcards
amplitude
the maximum distance moved from the rest point
frequency
number of cycles in 1s (Hz)
phase difference
the amount by which two waves are out of step with each other (0-2π)
wavelength
the length for one complete cycle (m)
wave speed
the distance traveled by a wave in 1s (ms^-1)
time for 1 wavelength
intensity
the energy per unit area per unit time (Wm^-2)
amplitude^2
SHM
the motion when acceleration has a magnitude proportional to displacement from a fixed point with a direction to a fixed point
a=-ω^2(x)
progressive waves
waves which travel whilst transferring energy. moving equivalent of a standing wave
transverse wave
vibrations at right angles to direction
longitudinal wave
vibrations parallel to direction
natural frequency
characteristic frequency with which a system oscillates about its equilibrium
damped oscillations
oscillations that eventually die due to dissipation of energy by friction, viscosity or other means
resonance
a condition when a vibrating system responds with maximum amplitude to an external force
critical damped
when the oscillations stop the soonest
Hooke’s law
F=kx
Energy stored=.5kx^2
Electromagnetic spectrum
Gamma 10^-15 X-Ray 10^-12 UV 10^-9 Visible 10^-7 Infra Red 10^-5 Microwaves 10^-2 Radio 10
Ray
Direction of the wave
Wavefront
Joins points of same phase
Principle of superposition
When two waves meet, total displacement at at any point vector sum of individual displacements
Path difference
Difference in distance from wave source to observer
