Light

• light is a form of energy
• light travels in a straight line in a vacuum, but it can be bent by a lens
• the electromagnetic spectrum includes radio waves, microwaves, infrared, visible light, ultraviolet, x-rays, and gamma rays
• when white light passes through a prism, the colours disperse due to their wavelengths
• The law of reflection states that the angle of incidence is equal to the angle of reflection.
• For total internal reflection to occur, the angle of incidence must be greater than the critical angle and light must be travelling from a less dense medium to a more dense medium
• the angle of incidence is measured from the normal
• The shorter the wavelength, the greater the amount of refraction
• luminous objects produce their own light
• non-luminous objects cannot produce their own light
• the colour of an object is determined by what colour light reflects off the object and into our eye. All other colours are absorbed
• dispersion of white light is when light is split into its respective colours by a prism
• red has the longest wavelength and the lowest frequency
• violet has the shortest wavelength and the highest frequency
• in a transverse wave, the particles move up and down while the energy is moving at right angles to the direction of the wave
• light is a form of electromagnetic energy