An IGCSE physics class is investigating how the design of a spring affects its extension.
Each student has access to a variety of springs made of different wire thicknesses, a set of standard slotted masses, a metre rule, and other common laboratory clamp stands and accessories.
A student decides to investigate how the thickness (diameter) of the wire from which the spring is wound affects the extension produced by a load.
Suggest three key variables in this investigation that should be kept constant.
The original length of the spring is denoted by l0l_0l0 and the length with a load attached is denoted by lll. State how a student ensures that the measurements of l0l_0l0 and lll are comparable.
It is often not possible to position a metre rule immediately adjacent to the spring. Describe how a student can overcome this issue to obtain an accurate measurement of the length lll.
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.