Which statement is true about an experiment where Brownian motion is demonstrated using pollen grains suspended in water?
The experiment makes it possible to see the motion of water molecules under a light microscope.
The motion is caused by the collisions of pollen grains with each other.
The motion is caused by collisions between water molecules and pollen grains.
The motion occurs because water contains a mixture of molecules with different isotopic masses.
48 exam-style questions on AQA A Level Physics Thermal physics (A-level only), covering Thermal energy transfer (A-level only), Ideal gases (A-level only), and Molecular kinetic theory model (A-level only). Each one has a worked solution and a mark scheme showing where the marks go.