Term 2 2012

In this term, we started on new physics topics like reflection, refraction, lenses and light.

Reflection

-occurs when rays of light strike a surface and changes its direction

-incident ray, reflected ray, point of incidence appears when reflection occurs

Types of reflection

Specular reflection- occurs on smooth surface

Diffused reflection-occurs on rough surface

Refraction

-When light is transmitted through a medium and bends

-Degree of bend of light depends on the optical density of medium

-IMPT FORMULAS: sin i/ sin r = refractive index, refractive index = 1/sin c

Lenses

This topic is slightly similar to the previous, where virtual and real image is involved once again. There are two types of lenses: converging and diverging lenses.

1)Optical centre- centre point of lens
2)Principal axis- line passing straight through optical centre
3)Principal focus (F) - point where all rays converge towards after refraction
4)Focal length- distance between principal focus and optical centre.