A lens is designed to do what to light?
Disperse light
Reflect light
Refract light
What type of lens is thicker in the middle than at the edges?
Convex
Diverging
Concave
Which type of lens causes light rays to diverge?
Converging
Which type of lens is used in a camera?
What is the name given to the distance between the optical centre of a lens and the principal focus?
The principal axis
The focal length
The principal focus
What happens to a ray of light incident on the optical centre of a lens?
It is bent towards the principal focus F
It passes straight through without being bent
It is bent away from the principal focus F
A lens has a focal length of 10 cm. An object is placed 5 cm in front of the lens. What are the properties of the image formed by the lens?
Real, enlarged, inverted
Virtual, enlarged, inverted
Virtual, enlarged, upright
What types of images do convex lenses form?
Virtual images only
Real images only
Both real images and virtual images
What does a long-sighted person need glasses to see?
Distant objects
A car number plate 30 m away
Writing in a book
What type of lens corrects short sight?
A plane lens
A diverging lens
A converging lens