A student observes tiny pollen grains suspended in water under a microscope. The pollen grains are seen to move in a continuous, random, and jerky motion, known as Brownian motion.
Explain what causes this random motion of the pollen grains, referring to the particles involved.
151 exam-style questions on CIE IGCSE Physics 2.1.2a Particle structure and motion in solids, liquids and gases. Each one has a worked solution and a mark scheme showing where the marks go.