Core
Light is a type of energy that we can perceive with our eyes.
When atoms are heated up they vibrate and emit photons.
These photons travel as a wave and we can see them as their wavelength lies in the visible part of the Electromagnetic Spectrum.
This spectrum comprises of all types of the different types of energy that are distributed in waves. Infra-red is an example that is emitted by hot objects.
Light travels in straight lines and it is this phenomena which means we cannot see around corners and that causes shadows.
As light has predictable properties, the study of optics (which is what physicists call this study, explores the different properties of light.
Ray diagrams are drawings that help us understand how light:
These diagrams allow us to help predict where images are in reality, predict the relative size of objects and even predict the type of material that light passes through.
Scientists can use light to determine a distant stars mass, age, temperature and even gravity!
Ray diagrams have the following common features:
When a light ray hits a surface it can either be:
Complete the practical activity in the booklet, draw the graph and answer the question - do our findings prove the law of reflection?