When light below the threshold frequency shines on a metal, its photons don’t have enough energy to free electrons from the surface. Each photon transfers its energy to just one electron, so if that energy is less than the metal’s work function, no ...

For comprehensive Physics tutorial videos, worked examples, exam questions, quizzes and tracked progress, go to https://payhip.com/GradeAPhysics Use this code to get 30% discount: PHYSICS-30   Challenge Question For a steel cable, the...

The critical angle for an optical fibre is 60°. Light travels through the fibre 2.0x10^8 ms-1 and the length of the fibre is 20 km. Calculate the difference in the time taken for the light to travel through the fibre by a light b...

The sketch shows how the current detected by a photocell circuit varies with the potential difference applied across the plates. a) Explain why the current is zero at the stopping potential. (2) b) Explain why the current increases to a maximum...

10 Tips to Improve Your A-Level Physics Grade (Year 12) 1. Focus on Getting the Basics Right Early Year 12 topics like mechanics, electricity and waves form the foundation of A-Level Physics. If these are weak now, Year 13 becomes much harder. 2.  L...

10 Tips to Improve Your A-Level Physics Grade (Year 13) 1. Use Past Papers as Your Main Revision Tool At Year 13, the fastest way to improve your A-Level Physics grade is by practising real exam questions. 2.Learn Mark Scheme Language Top grades dep...