CAIE A-Level Physics 17.1.4 SHM Velocity Equations
Practise using v = v₀ cos ωt or v = ±ω√(x₀²−x²) to calculate SHM velocity, then interpreting sign, amplitude, displacement and maximum speed.
- Syllabus
- 2028–2030
- Course
- Physics 9702
- Level
- A2
Practise using v = v₀ cos ωt or v = ±ω√(x₀²−x²) to calculate SHM velocity, then interpreting sign, amplitude, displacement and maximum speed.
A spring is hung vertically from a fixed point. A mass M is hung from the other end of the spring, as illustrated in Fig. 3.1.

Fig. 3.1
The mass is displaced downwards and then released. The subsequent motion of the mass is simple harmonic.
The variation with time t of the length L of the spring is shown in Fig. 3.2.

Fig. 3.2
Use data from Fig. 3.2 to determine, for the motion of the mass:
the maximum speed
maximum speed = ms−1
v0=ωX0
C1
=15.7×2.5×10−2=0.39 m s−1
A1
or
tangent drawn at steepest part and working to show attempted calculation of gradient
(C1)
leading to v0=0.39 m s−1 (allow ± 0.15 m s−1 )
(A1)