1. The graphs shows a straigtht line through the origin and has a negative gradient. It is of the form a = - w2x , hence it is shm
b) AT the top, mg - R = ma. When the sand loses contact R = O, hence a = g
ii) from the graph , amplitude = 3.8 mm when acceleration = 9.81 ms-2.
2. The speed at x = 0.02 m is 0.144 ms-1
aii) The max ke = 1.23 x 10-3J( calc max v = wxo)
3. a) The effect is resonance.
b)i) max velocity = 1.21 ms-1 and max acc = 91 ms-2
ii) time = T/4 = 0.0208 s
