Stuck on find the frequncey and max speed of a wave, urnt

AI Thread Summary
The discussion centers around solving for the frequency and maximum speed of a transverse wave described by the equation y = 6.1 sin(0.010x + 3.0t). The amplitude is correctly identified as 6.1 cm, and the wavelength is debated, with one participant noting it should be 628 cm rather than 200 cm due to the wave number. To find the frequency, participants suggest using the angular frequency, which is 3.0, and the relationship between speed, wavelength, and frequency. The maximum transverse speed can be determined using the formula Aω, where A is the amplitude and ω is the angular frequency.
mr_coffee
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Hello everyone! I got some parts of this question right but are stuck on others. Here is the problem:
The equation of a transverse wave traveling along a very long string is given by y = 6.1 sin(0.010x + 3.0t), where x and y are expressed in centimeters and t is in seconds. Determine the following values.

(a) the amplitude
6.1
(b) the wavelength
200
(c) the frequency
?
(d) the speed
?cm/s
(e) the direction of propagation of the wave
+x
[-x]
+y
-y

(f) the maximum transverse speed of a particle in the string
cm/s

From the equation i got the amplitude, From the wave # i got the wave length.
K = wave #
K = 2*pi/WaveLength
WaveLength=200

but now I'm stuck on how I'm suppose to find the frequency?
If i could find the period, i could find the frequency. or if i could find the angular frequency I also could find the frequnecy. Once I find frequency, finding speed would be easy. V = WaveLength*frequncey

How do you know the propagation of the wave? I got it right but it was through guessing.
-x was the answer.


Also how would i find the max speed? Does it invovle me taking the derivative of the function?

Thanks!
 
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mr_coffee said:
Hello everyone! I got some parts of this question right but are stuck on others. Here is the problem:
The equation of a transverse wave traveling along a very long string is given by y = 6.1 sin(0.010x + 3.0t), where x and y are expressed in centimeters and t is in seconds. Determine the following values.

(a) the amplitude
6.1
(b) the wavelength
200
(c) the frequency
?
(d) the speed
?cm/s
(e) the direction of propagation of the wave
+x
[-x]
+y
-y

(f) the maximum transverse speed of a particle in the string
cm/s

From the equation i got the amplitude, From the wave # i got the wave length.
K = wave #
K = 2*pi/WaveLength
WaveLength=200

but now I'm stuck on how I'm suppose to find the frequency?
If i could find the period, i could find the frequency. or if i could find the angular frequency I also could find the frequnecy. Once I find frequency, finding speed would be easy. V = WaveLength*frequncey

How do you know the propagation of the wave? I got it right but it was through guessing.
-x was the answer.


Also how would i find the max speed? Does it invovle me taking the derivative of the function?

Thanks!

The angular frequency \omega is simply what multiplies the time ! (so 3.0).

A traveling wave moves to the right if the x and t terms have opposite signs.

You could find the velocity by taking the derivative with respect to time and then find when the velocity is max, but the quick answer is that the max speed of a particle is A \omega

Patrick
 
THanks a lot man! WOrked perfectly!
 
What makes you think that the wavelength is 200 [cm?]?
k is the quantity that multiplies x , so wavelength = 2 pi /.01 = 628.
 
lightgrav said:
What makes you think that the wavelength is 200 [cm?]?
k is the quantity that multiplies x , so wavelength = 2 pi /.01 = 628.

Good point, lightgrav... I did not check the parts that he said he had no problems with. He forgot the factor of pi.

Pat
 
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