(a)[2]
The mass is in equilibrium. Explain what equilibrium means by referring to the forces acting on the mass.
(b(i))[1]
The mass is pulled downward and then let go at time $t = 0$. It moves up and down in oscillation. The change with $t$ of the displacement $d$ of the mass is shown in Fig. 3.2. Use Fig. 3.2 to give a time, one for each case, when the mass has maximum speed.
(b(ii))[1]
Use Fig. 3.2 to give a time when the elastic potential energy stored in the spring is greatest.
(b(iii))[1]
Use Fig. 3.2 to give a time when the mass is in equilibrium.
(c(i))[2]
State and explain whether the spring follows Hooke’s law.
(c(ii))[2]
Show that the force constant of the spring is $26\,\text{N m}^{-1}$.
(c(iii))[3]
A $0.40\,\text{kg}$ mass is attached to the spring. Calculate the energy stored in the spring.