Hello again! I have a few questions regarding mathematical descriptions of waves. what does it mean when a wave is propagating to the left? and how would i go about drawing that? do i just put a negative sine in front of the function? (for example sin(x) is original, -sin(x) is propagating to the left? Another question ...so I have the equation: y(x,t) = Acos[2pi/lamda(x-vt)] which is the wave function equation. how would i go about solving the expression for the transverse velocity and maximum speed (of particle on string for example). I don't want answers, just help starting this problem. I'm not a physics major or anything so if you dont mind using simpler explanations (though i appreciate any help you can give me!!) and lastly... A continuous succession of sinusoidal wave pulses are produced at one end of a very long string and travels along the length of the string. I am given the frequency, amplitude, and wavelength. I'm trying to work with the function: y(x,t) = Acos2pi[(x/lamda) - (t/T)] I know: T = 1/f & lamda = v/f & w=2f*pi=vk I plug in all of my data for A, x, lamda, and T. However, I want to find the amount of time needed for the wave to travel a certain distance (which is also given) how would I go about doing that? Do i sent two functions equal to each and solve for t? I tried, but it doesn't make sense to me and I don't even know if that is a legal move. Thanks you guys!