# Finding the slop of a string (Waves)

1. Apr 7, 2008

### cse63146

1. The problem statement, all variables and given/known data

Wave motion is characterized by two velocities: the velocity with which the wave moves in the medium (e.g., air or a string) and the velocity of the medium (the air or the string itself).

Consider a transverse wave traveling in a string. The mathematical form of the wave is

$$y(x,t) = Asin(kx - \omega t)$$

Find the slope of the string $$\frac{dy(x,t)}{dx}$$ as a function of position x and time t.
2. Relevant equations

3. The attempt at a solution

So to find the slope of that equation, I would just need to take it's derivative. x is the variables, and $$\omega$$, A, t are constants. I would also need to use the chain rule when doing the derivative of sin.

So I get: $$\frac{dy(x,t)}{dx} = (Acos(kx - \omega t))*(k - \omega t)$$

but it says I'm wrong. Any suggestions where I went wrong?

2. Apr 7, 2008

### robphy

Check your result for consistency of units.

3. Apr 7, 2008

### Integral

Staff Emeritus
$$\frac d {dx} ( kx- \omega t)$$ = ?

4. Apr 7, 2008

### cse63146

would I treat the x as a variable and t as a constant?