Year 9 Light and Waves

Interpret a transverse-wave diagram by identifying its crest, trough, amplitude, and wavelength.

Distinguish transverse waves from longitudinal waves using the direction of vibration, including identifying compressions and rarefactions.

Use the wave equation v = fλ to solve one-step problems involving wave speed, frequency, or wavelength with appropriate units.

Describe visible light as electromagnetic radiation, place it within the electromagnetic spectrum, and order ROYGBIV from longest to shortest wavelength.

Predict whether light will be transmitted, absorbed, reflected, or blocked by a material, and use straight-line ray paths to explain shadow formation.

Apply the law of reflection in labelled ray diagrams using the incident ray, reflected ray, normal, angle of incidence, and angle of reflection.

Compare the ray behaviour and common uses of plane, concave, and convex mirrors, using terms such as real, virtual, inverted, laterally inverted, enlarged, and diminished where appropriate.

Predict whether a light ray bends towards or away from the normal when it enters a different medium, and distinguish convex from concave lenses by how they refract parallel rays.