The Displacement of a String Carrying a Traveling Sinusoidal Wave $\phi$

Multiple Choice

The displacement of a string carrying a traveling sinusoidal wave is given by At time t = 0 the point at x = 0 has a velocity of 0 and a positive displacement.The phase constant $\phi$ is:

A) 45 $\degree$
B) 90 $\degree$
C) 135 $\degree$
D) 180 $\degree$
E) 270 $\degree$