Waves, finding frequency, wavelength, and speed

AI Thread Summary
To solve the wave equation D(y,t)=(5.2cm)sin(5.5y+72t), the first step is to identify the wave parameters. The coefficient 5.5 relates to the wavelength, calculated using the formula 5.5 = 2π/λ, leading to a wavelength of 1.14 m. The frequency can be derived from the angular frequency (72 rad/s) using the relationship between frequency and period, resulting in a frequency of 11.5 Hz. Finally, the wave speed is determined by the formula v = fλ, yielding a speed of 13.1 m/s. Understanding these relationships is crucial for solving wave problems effectively.
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I am assigned the even problem for homework, but I am lost, so I found an odd problem with the same type of question and has the answer... I just need to know how the calculations are done

Homework Statement



The displacement of a wave traveling in the negative y-direction is D(y,t)=(5.2cm)sin(5.5y+72t), where y is in m and t is in sec. Find the frequency, wavelength and speed of the wave

Homework Equations



D(x,t) = A sin[2π (x/λ -t/T) + Φ]

The Attempt at a Solution



I have no clue, the answers are:

11.5 Hz
1.14 m
13.1 m/s
 
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Well I'll help get you started.

By comparing the two equations, you know that

5.5 = \frac{2\pi}{\lambda}

So you can easily find the wavelength.

How can you find the frequency in a similar manner? What is the relationship between frequency and period? When you have the frequency and wavelength, what is the relationship between those and velocity?
 
Thanks!
 
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