9702 · 11.2
Fundamental particles
Dive into the minuscule world that forms everything around us! In this lesson, we'll unravel the **fundamental particles** that build atoms, from the familiar **protons**, **neutrons**, and **electrons** to the elusive **quarks** and **leptons**. Understanding these tiny components is key to grasping nuclear reactions and the very fabric of the universe. This pilot aligns with **Senpai Corner** AS notes (2025–2027) for topic **11.2**.
Need to know
What you need to know
- **Strong Nuclear Force:** The strongest force, but has a very short range (~10⁻¹⁵ m). It holds quarks together to form protons and neutrons, and binds protons and neutrons together in the nucleus. It affects hadrons.
- **Electromagnetic Force:** Weaker than the strong force, but has an infinite range. It acts between electrically charged particles. It holds atoms and molecules together.
- **Weak Nuclear Force:** Weaker still, and has an even shorter range (~10⁻¹⁸ m). It is responsible for radioactive decay, as it can change the flavour of quarks and leptons (e.g., in beta decay).
- **Gravitational Force:** The weakest of the four forces, but has an infinite range. It acts between all particles with mass. While dominant on a cosmic scale, its effect is negligible at the subatomic level.
Explanation
Fundamental particles
- **Strong Nuclear Force:** The strongest force, but has a very short range (~10⁻¹⁵ m). It holds quarks together to form protons and neutrons, and binds protons and neutrons together in the nucleus. It affects hadrons.
- **Electromagnetic Force:** Weaker than the strong force, but has an infinite range. It acts between electrically charged particles. It holds atoms and molecules together.
- **Weak Nuclear Force:** Weaker still, and has an even shorter range (~10⁻¹⁸ m). It is responsible for radioactive decay, as it can change the flavour of quarks and leptons (e.g., in beta decay).
- **Gravitational Force:** The weakest of the four forces, but has an infinite range. It acts between all particles with mass. While dominant on a cosmic scale, its effect is negligible at the subatomic level.