What happens when light hits an object? Science 10 – Optics

How do we show the direction in which light is travelling? To trace the straight-line path that light travels, scientists use an arrow called a ray You will use diagrams that involve rays (ray diagrams) to help you understand and make predictions about the way light behaves

Reflection Reflection is the process in which light ‘bounces off’ a surface and changes direction How would you use a ray diagram to illustrate this?

Absorption Absorption is the process in which light energy remains in an object and is converted into heat Objects appear the colour they are because they absorb all colours of the spectrum except the one our eyes see (it is reflected) The black ‘E’ below appears black because it absorbs all of the light that hits it (no light hits your eyes) E

Absorption/Reflection

Transmission Transmission is the process in which light travels through an object and continues travelling Different objects transmit different amounts of light There are 3 ways to describe transmission: Transparent Translucent Opaque

Transparent If light is transmitted directly through an object without any change in direction, the object is transparent What is an example of a transparent object?

Translucent If light can penetrate an object but it is scattered in many directions, the object is translucent What is an example of a translucent object?

Opaque If an object absorbs or reflects light only and no light penetrates it, the object is opaque What is an example of an opaque object?

Transparent/Translucent/Opaque

Ray Diagrams If you had to draw ray diagrams for objects that were transparent, translucent and opaque, what would they look like?? Transparent Translucent Opaque

Ray Diagrams