A student measures the spring constant using a graph of force against extension. The student plots the total spring length instead of the extension. The spring obeys Hooke's law. Which describes the graph and its gradient?
The line misses the origin; its gradient still gives the spring constant.
The line passes through the origin; its gradient still gives the spring constant.
The line passes through the origin; its gradient gives an incorrect spring constant.
The line misses the origin; its gradient gives an incorrect spring constant.
102 exam-style questions on Edexcel GCSE Physics 15.1 Forces and springs, covering 15.1.1 Elastic and inelastic distortion, 15.1.2 The spring constant, 15.1.3 Work done in stretching a spring, and 15.1.4 Linear and non-linear force–extension. Each one has a worked solution and a mark scheme showing where the marks go.