Mechanical Waves

Energy of a Wave

spread speed of the wave

General formula

lineal density formula

Mechanical Waves

Anatomy of a wave

The crest is the maximum positive amount of displacement from the equilibrium point.

The trough is the maximum negative amount of displacement from the equilibrium point.

The wavelength (λ) is the length from crest to crest or trough to trough and corresponds to one cycle.

The amplitude (A) is the distance from the equilibrium point to the crest.

A mechanical wave is the one that needs a medium to travel.

Transverse wave happens when the particles in a medium vibrate perpendicular to the direction of the wave’s motion.

Longitudinal wave happens when the particles in a medium vibrate in the same direction of the wave’s motion.

Speed of a wave

formula intensity

frequency increases more antinodes

resonance frequency of a fixed string

V=λf

Where:

V= speed (m/s)

λ= wavelength (m)

f = frequency (1/s)

µ=m/L

Where:

m= mass of the rope (kg)

L= length (m)

v= (raiz cuadrada f/µ)

Where:

F: tension force (N)

µ: lineal density (kg/m)

SI units speed m/s.

I=(2(pi)2)vpf2A2

Where:

I= wave’s intensity (Watt/m2)

v= speed of propagation (m/s)

ρ= density of the medium (kg/m3)

f= Frequency (Hz)

A= amplitude (m)

spread speed