The students performed various experiments in remote mode — from physics experiments such as calculating the gravitational constant g using a pendulum to finding the focal length of a convex lens.

We compare and contrast concave and convex lenses by drawing ray diagrams.

Learn about refraction, ray diagrams and how convex lenses bend light rays with this guide for KS3 physics students aged 11-14 from BBC Bitesize.

With a concavo-convex lens the convex surface gives an inward pointing coma, and the concave surface an outward pointing coma.