Have two questions about waves. 1. If a rope with mass "m" is suspended from the ceiling and a wave puse is produced at the lower end of the rope and will travel upwards. Will the speed of the wave change, and if so, will it increase or decrease? My taughts: I was trying to figure out if the tension itself will increase or not, because the speed will depend on the tension, right?. so lets say the pulse is travelling up the rope, then i taught that the mass behind the pusle will increase(because more length) and gravitational force will make the tension increasse, therefore the wavespeed should increase...right?) 2. If the displacement of a tight string is given by : y(x,t) = A cos((2pi/constant)*(x-vt)) find a expression for vy(that is v in the y direction) at which a piece of string travels. What is the maximum value of vy? When is the maximum value greater than the wave propagation speed v? my taught: I don't have a clue about this question though, don't knwo where to start, so if someone could give me a push in the right direction. Thanx for the help!