Light

• Light travels already as a transverse wave and is a form of energy that our eyes can detect.
• Light is an example of an electromagnetic wave which can travel through a vacuum at a speed of approximately 300,000 kilometres per second (3 x 10^8 metres per second). The speed of light is usually denoted by c.
• Reflection is when light bounces off an object. All reflected light obeys the law of reflection – the angle of incidence equals the angle of reflection.
• Refraction is when light changes direction as it enters a different medium. It occurs because light travels slower in denser mediums.

Wave-Particle Duality

• Light possesses both wave-like and particle-like properties, a phenomenon known as the wave-particle duality.
• When light interacts with matter, it exhibits particle-like properties (photons), whereas when it propagates, it exhibits wave-like properties.
• The energy of a photon of light is given by Einstein's equation E=hf where 'h' is Planck's constant and 'f' is the frequency of light.

Visible Spectrum

• The visible spectrum is the component of the electromagnetic spectrum that is visible to the human eye. It extends from approximately 400 nanometres (violet light) to 700 nanometres (red light).
• When white light passes through a prism, it disperses into all the colours of the visible spectrum. This is known as dispersion.
• Different colours of light correspond to different frequencies and wavelengths; red light has the longest wavelength and lowest frequency, while violet light has the shortest wavelength and highest frequency.

Light Interference and Diffraction

• Light waves can interfere with each other, creating regions of constructive (increased amplitude) and destructive (decreased amplitude or cancellation) interference.
• The phenomenon of light bending around corners and spreading out is known as diffraction. The amount of diffraction depends on the wavelength of light.

Optics

• Mirrors, lenses, and prisms are optical devices that manipulate light by reflection, refraction and dispersion respectively.
• A mirror creates an image by reflecting light. The shape of the mirror (concave, convex or flat) affects the size, orientation, and type (virtual or real) of the image.
• Lenses work by refracting light. Converging lenses bring light to a focus, forming a real image, while diverging lenses spread light out, forming a virtual image.
• A prism splits white light into its constituent colours via dispersion.

Remember to use your knowledge of light properties, reflection, refraction and the behaviour of light through various mediums in order to work out practical scenarios and solve problems. Your understanding of the wave nature of light, including principles of interference and diffraction, is also useful for explaining various light phenomena. Learning the way light is manipulated in optical devices can further enhance your ability to predict and analyse the behavior of light in different situations.