Physics Paper 1 · P4 · Lesson 4.7
Keep the top numbers and bottom numbers balanced.
A nuclear equation tracks the nucleus before and after decay. The mass numbers balance, and the atomic numbers balance. In each example, the element symbols you need are supplied.
An electron is written with mass number 0 because it contains no protons or neutrons; it still has a tiny mass.
No timer. Read the explanation after each answer.
Daily 5 · Core exam practice · Higher Tier questions · A4 revision sheet
Lessons 4.1–4.10 cover the core. Lesson 4.11 is Higher Tier only. Daily 5 practises core facts. Answer positions are shuffled on each new attempt; lessons begin with very simple questions.
AQA Combined Science Trilogy specification · 6.4.2.2. Original notes, questions and diagrams. Experimental numbers are illustrative.
Photos: Geiger counter by Boffy b, enhanced by Marco Plassio; caesium source by Wusel007, enhanced by Partynia, both CC BY-SA 3.0. Rutherford at McGill, 1905, unknown photographer / Wellcome Images, public domain. Photos displayed without cropping or other alterations.
