6.6.2.5 Lenses Flashcards
1
Q
How does a lens form an image?
A
- refracts light
2
Q
What happens in a convex lens?
A
- parallel rays of light brought to a focus at principal focus
3
Q
What is the focal length?
A
- distance from lens to principal focus
4
Q
What are ray diagrams used for?
A
- to show formation of images by convex and concave lenses
5
Q
What can the image produced by a convex lens be?
A
- real or virtual
6
Q
What is the image produced by a concave lens?
A
- always virtual
7
Q
What is the equation for magnification?
A
- magnification = image height / object height
8
Q
What are the units for magnification?
A
- none
- it is a ration
9
Q
What are the units for image and object height?
A
- should be mm or cm
