Lenses

what are the two types of lenses

Convex and concave

What are Concave lenses

A lens which caves inwards

What are convex lenses

A lease which bulges outwards

What do convex lenses do

Refracts parallel rays of light inwards to a single point (focal point)

What do concave lenses do

Refracts parallel rays of light outwards (disperses the light)

Focal length

Distance between focal point and centre of the lens

The shorter the focal length….

The more powerful the lens will be (refracts light more strongly)

How are images formed?

Formed at points where all the light rays from a particular point on an object, appear to come together

How are Real images formed

When light rays actually do come together to form the image

How are virtual images formed

When the light rays don’t come together where the images appear to be

What type of lenses do magnifying glasses use

Convex lenses

How do magnifying glasses work

By creating a visual upright image that is larger than the object and is on the same side of the lens as the object

What is required for the object being magnified

It must be close to the lens than the focal length

Magnification equation

Magnification = image height/ object height