Final answer:
The wave speed is 45.12 m/s, the frequency is 7.14 Hz, and the wave number is 1.31 mμ. At t=0.42s and x=5.2m, the displacement of the string is 1.8cm.
Step-by-step explanation:
The wave function D(x,t) can be written as D(x,t) = (3.6 cm) x sin[2π(x/(4.8 m) + t/(0.14 s) + 1)].
The wave speed can be calculated using the formula v = ω/k, where ω is the angular frequency and k is the wave number. In this case, the wave speed is v = 2π/0.14 = 45.12 m/s.
The frequency of the wave can be found using the formula f = ω/2π. In this case, the frequency is f = 1/0.14 = 7.14 Hz.
The wave number can be calculated using the formula k = 2π/λ. In this case, the wave number is k = 2π/4.8 = 1.31 mμ
At t = 0.42 s and x = 5.2 m, the displacement of the string can be calculated by substituting these values into the wave function. The displacement is D(x,t) = (3.6 cm) x sin[2π((5.2 m)/(4.8 m) + (0.42 s)/(0.14 s) + 1)] = 1.8 cm.