A harmonic wave on a string is described by
Y (x, t) = 0.1 sin (300t +0.01x + л/3) mm, where x is in cm and t is in seconds.

a) Does the wave represent a travelling wave or a standing wave?
b) What is the direction of its propagation?
c) What is its period?
d) What is its wavelength?
e) What is the amplitude of the particle?

Respuesta :

[tex]\huge{\bold{\orange{\underline{ Solution }}}}[/tex]

Given :-

A harmonic wave on a string is described by

[tex]\sf{ Y( x, t) = 0.1 sin(300t + 0.01x + π/3)}[/tex]

  • x is in cm and t is in seconds

Answer 1 :-

Equation for travelling wave :-

[tex]\sf{ Y( x, t) = Asin(ωt + kx + Φ)...eq(1)}[/tex]

Equation for stationary wave :-

[tex]\sf{ Y( x, t) = Acos(ωt - kx )...eq(2)}[/tex]

Given equation for wave :-

[tex]\sf{ Y( x, t) = 0.1 \:sin(300t + 0.01x + π/3)...eq(3)}[/tex]

On comparing eq(1) , (2) and (3)

We can conclude that, Given wave represent travelling wave.

Answer 2 :-

From solution 1 , We can say that,

[tex]\sf{ Y( x, t) = 0.1 \: sin(300t + 0.01x + π/3).}[/tex]

It is travelling from right to left direction

Hence, The direction of its propagation is right to left that is towards +x direction.

Answer 3 :-

Here, We have to find the wave period

We know that,

Wave period = wavelength / velocity

Wave equation :-

[tex]\sf{ Y( x, t) = 0.1 \:sin(300t + 0.01x + π/3).}[/tex]

  • ω = 300rad/s
  • k = 0.01

We know that,

[tex]\sf{v =}{\sf{\dfrac{ ω}{2π}}}{\sf{\: and\:}}{\sf{ λ =}}{\sf{\dfrac{ 2π}{k}}}[/tex]

Subsitute the required values,

[tex]\sf{ wave\: period =}{\sf{\dfrac{ 2π/k}{ω/2π }}}[/tex]

[tex]\sf{ wave \:period = }{\sf{\dfrac{k}{ω}}}[/tex]

[tex]\sf{ wave\: period =}{\sf{\dfrac{ 0.01}{300}}}[/tex]

[tex]\sf{ wave\: period = 0.000033\: s}[/tex]

Answer 4 :-

The wavelength of given wave

[tex]\bold{ λ = }{\bold{\dfrac{2π}{k}}}[/tex]

Subsitute the required values,

[tex]\sf{ λ = }{\sf{\dfrac{2 × 3.14 }{0.01}}}[/tex]

[tex]\sf{ λ = }{\sf{\dfrac{6.28}{0.01}}}[/tex]

[tex]\sf{ λ = 628 \: cm }[/tex]

Answer 5 :-

We have wave equation

[tex]\sf{ Y( x, t) = 0.1 sin(300t + 0.01x + π/3).}[/tex]

Travelling wave equation :-

[tex]\sf{ Y( x, t) = A\:sin(ωt + kx + Φ)...eq(1)}[/tex]

Therefore,

Amplitude of the wave particle

[tex]\sf{ A = 0.1 \: cm}[/tex]

Hence, The amplitude of the particle is 0.1 cm