Physics 7408/3BD June 2020

The AQA A-level Physics Paper 3B (November 2020), Option D (Turning Points in Physics), explores foundational discoveries in modern physics. Topics include JJ Thomson’s cathode ray experiments, specific charge determination, and the role of electric and magnetic fields in particle deflection. Key areas involve black-body radiation, Planck’s quantum hypothesis, and Einstein’s photoelectric theory. The paper also examines quantum tunneling via scanning tunneling microscopy, de Broglie wavelength calculations, and relativistic effects such as time dilation and length contraction. Keywords: AQA Physics, turning points, cathode rays, photoelectric effect, black-body radiation, quantum tunneling, relativity.