[填空题]
A 2.0 kg object is attached to a spring and vibrates vertically.
The graph below shows the variation of the acceleration of the object with the displacement x.
1.(1)State and explain whether or not the oscillation of the mass is simple harmonic motion.
(2)On the figure above draw an arrow to show the direction of the acceleration of the mass which is displaced by x.
2.(1)Show that the slope of the graph equals to $\frac{-k}{m}$
(2)By using the graph calculate the spring constant, $k$ of the spring.k= $Nm^{-1}\,kgs^{2}$
3.For the same spring-mass system, show that the acceleration of the object is$10\,cms^{−2}$ when the mass is displaced by 0.12 cm. a≈ $cms^{-2}$
