Q11. The graph of displacement vs time for a small mass 9.4g oscillating at the end of a spring is shown in the figure. X1 (a). Find the frequency of the oscillation. (2 points) 0.9 cm 0.5 cm (b). Find the spring constant k of the spring. (3 points) 0.72 s (c). Write down the equation for displacement x as a function of time. (with cosine function) (3 points) (d). If the spring is replaced with another spring with heavier mass while the spring constant remains the same, will the frequency of the oscillation increase, decrease or remain the same? (2 points) (e) Find the transverse velocity of the mass at t = 5s. (3 points)