A book rests on a table. A student says that the weight of the book and the normal contact force from the table are an interaction pair. Which statement shows why the student is wrong?
The two forces act on the same object rather than on two objects.
The two forces are different in size, so they cannot be a pair.
The two forces act in the same direction, so they cannot be a pair.
The two forces are both contact forces, so they cannot be a pair.
40 exam-style questions on AQA GCSE Physics 5.1 Forces and their interactions, covering 5.1.1 Scalar and vector quantities, 5.1.2 Contact and non-contact forces, 5.1.3 Gravity, and 5.1.4 Resultant forces. Each one has a worked solution and a mark scheme showing where the marks go.