A model predicts that Venus can be seen only as a crescent or as a dark disc. Another model predicts that Venus can also appear nearly fully illuminated.
Repeated telescope observations show Venus nearly fully illuminated.
Which is the best conclusion?
The first model remains consistent; the second conflicts with evidence.
Both models remain consistent because Venus reflects light from the Sun.
The first model conflicts with evidence; the second remains consistent.
Neither model remains consistent because Venus changes its appearance.
80 exam-style questions on Edexcel GCSE Physics 7.1 The Solar System and gravity, covering 7.1.1 Weight and g on different bodies in space, 7.1.2 The Solar System, 7.1.3 Changing ideas about the Solar System, 7.1.4 Orbits of moons, planets, comets and satellites, and 7.1.5 Gravity and orbital motion. Each one has a worked solution and a mark scheme showing where the marks go.