Physics - SHM, Wave phenomena, Standing Waves, Resonance & Damping, Doppler Effect

a system is said to be undergoing SHM when:

• the acceleration/force is proportional to the displacement from the equilibrium

• the acceleration is directed opposite to the displacement and towards the equilibrium

time period, T

time taken for 1 oscillation

frequency, f

the # of oscillations per unit time

phase, ∅

the difference in relative cycles of two waves

SHM KE

½ m⍵²(x0²-x²)

transverse waves

particles oscillate perpendicular to the direction of energy transfer

longitudinal waves

particles oscillate in the same plane/axis as the direction of energy transfer

wavefront

joins points of equal phase

ray

points in the direction of energy transfer

wave intensity

k(amplitude²/distance²)

wave enters from less dense to dense

towards the normal

wave enters from dense to less dense

away from the normal

refractive index

the ratio of the speed of light in a vacuum to the speed of light in the medium

critical angle

refracted light forms a 90° angle with the normal

TIR

happens when light enters beyond the critical angle

-

caused by the interference of two oppositely moving waves

principle of superposition

when two waves meet the resultant displacement is the sum of the individual displacements

standing waves

waves which store energy that are achieved when two waves traveling in opposite directions along the same line at the same frequency superpose

ƛn for both fixed or both open ends

2L/n

fn for both fixed or both open ends

nV/2L

ƛn for one end open

4L/n

fn for one end open

nV/4L

resonance

when the frequency of an applied force equals the natural frequency, the system gains energy and the oscillation’s amplitude is at a maximum

damping

the reduction in energy and amplitude of oscillations due to resistive forces (frequency doesn’t change)

doppler effect

the perceived change in frequency when an emitter and an observer move relative to each other