A wave traveling along the x axis is described mathematically by the equation y = 0.17sin(8.5πt + 0.45πx), where y is the displacement (in meters), t is in seconds, and x is in meters. What is the speed of the wave?

2 answers

speed=wavelength*frequency
in the form y=Asin(2pif*t+2PIx/lambda)
so 2pif=8.5PI or f=4.25hz
and 2PI/lamba=.45PI
or lambda=2/.45=4.44

finally, speed=f*lambda=4.25*4.44=???m/s
Thank you so much! I had totally forgotton about the formula