A 0.20 kg0.20\text{ kg}0.20 kg mass is suspended from a vertical spring.
The mass is pulled downwards until the spring has extended by 15 cm15\text{ cm}15 cm from its unstretched length.
The spring constant of the spring is 80 N/m80\text{ N/m}80 N/m.
What is the magnitude of the initial acceleration of the mass when it is released? (Take g=9.8 m/s2g = 9.8\text{ m/s}^2g=9.8 m/s2.)
245 exam-style questions on CIE IGCSE Physics 1.5 Forces, covering 1.5.1a Forces, resultant force and motion, 1.5.1b Load–extension graphs and the spring constant, 1.5.1c Friction and drag, 1.5.1d Force, mass and acceleration, 1.5.1e Motion in a circular path, 1.5.2a Moment of a force, 1.5.2b Principle of moments and equilibrium, and 1.5.3 Centre of gravity and stability. Each one has a worked solution and a mark scheme showing where the marks go.