Is My Wave Equation Correct for These Parameters?

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The discussion centers on the correctness of a wave equation derived from given parameters: amplitude of 2 cm, wave vector of 502.7, and angular frequency of 125.7 Hz at time zero. The proposed equation is y = 0.02 sin(125.7 - 502.7x), which aligns with the general wave equation format y = A sin(wt ± kx). Participants clarify that the argument of the sine function must be dimensionless and emphasize the importance of correctly interpreting the time component in the equation. There is also a discussion about the relationship between frequency in Hz and angular frequency in radians, noting that at t=0, the angular frequency term becomes zero. Overall, the equation is generally accepted, but attention to detail regarding the time variable is advised.
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I needed to write an equation for a wave with:

amplitude : 2cm
wave vector : 502.7
angular frequency : 125.7 Hz
time : 0 sec

and I used the general equation for waves to come up with:

y = 0.02 sin (125.7 - 502.7x)

is that alright?
 
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What is the general equation you used (and what do the constants mean)?

Also, what do you mean by: wave vector = some number ?
 
y=A sin (wt\pmkx) is the formula where

A = amplitude
w = angular freq.
t = time
k = wave vector

wave vector doesn't have units as it's a vector quantity.. right?
 
rugapark said:
wave vector doesn't have units as it's a vector quantity.. right?

You might want to reconsider this statement. Displacement is a vector quantity, would you agree that displacement has a unit?

One hint - the argument of the Sine function must be dimensionless.

I agree with your general equation. However, using the conditions you gave (t=0) are you sure that you're happy with the time component of the argument? Remember your multiplying the angular velocity and time, with the time equal to zero. Are you sure this would give you the angular velocity back, like your expression suggests?

Kind Regards

Barny
 
What's given for frequency is Hz, usually represented by f. The radian frequency, w, is w=2*pi*f. However, the wave equation has w*t. If t is zero, then that product is zero, and there is no need to convert.
 
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