Answer: (a) y(x,t) = 0.0800 sin(7.85x + 6πt) meters
Remember y(0, 0) must equal 0.
(b) 0 = sin (.785 + φ)
Explanation: (a)
k = 2π/λ
k = 2π/0.800
k = 7.85 m-1
ω = 2πf
ω = 2π3
ω = 6π rad/sec.
y(x,t) = 0.0800 sin(7.85x + 6πt) meters
Remember y(0, 0) must equal 0.
(b)
We know that we must shift the wave so that y(0.100, 0) = 0
y(x,t) = 0.0800 sin(7.85x + 6πt + φ)
0 = 0.08 sin (7.85(0.1) + 0 + φ)
0 = sin (0.785 + φ)
φ = -0.785