# Sin Equation for Waves

dwn

## Homework Statement

A transverse wave travels on a string whose mass density is    kg/m.
The displacement (in meters) is given as a function of time and position as:

    D(x,t) = 1.5sin(3x-24t+90°)

What is the velocity and direction of the wave?
What is the speed of the particle located at x=8 and t=1?

## Homework Equations

Derivatives of the former.

$$∂^2D/∂t^2=v^2(∂^2D/∂x^2)$$

## The Attempt at a Solution

I took the partial derivatives with respect to both x and t. Applied them to the wave equation. But I don't understand how I'm supposed to get any figures to answer the questions above.

$$v=sqrt(-864sin(-24t)/(-13.5sin(3x))$$ ----> not sure what I do after this point.

Staff Emeritus