What Is the Phase Angle of a Wave Traveling on a String?

[physicsgrouch]

A transverse, sinusoidal wave is traveling along a string. It moves in the negative x-direction, and it has an amplitude of 5 cm. At time t=0, the point at x=0 is at a displacement of 4 cm and is traveling upward. What is the phase angle in degrees?

Homework Equations

x = A*cos([tex]\omega[/tex]*t+[tex]\phi[/tex])

The Attempt at a Solution

At t=0, [tex]\omega[/tex]*t = 0, so x = A*cos([tex]\phi[/tex]). Therefore, [tex]\phi[/tex] = arccos(x/A) = arccos(.8) = 36.87.

The acceleration is negative and the velocity is positive, so the angle is 360 - 36.87 = 323.13 degrees, right?

 

[physixguru]

The equation you just used is not trustworthy for waves.It can be only generalized to SHM.

You must use wave equations to be more sure in your answers.

y= A sin ( k*x-omega*t + phase angle)

 

[Moetasim]

Yes, that is correct. The phase angle in this scenario would be 323.13 degrees. The phase angle represents the starting point of the wave and is measured in degrees or radians. It is important in understanding the behavior and characteristics of the wave.