Converging Lenses Flashcards
1
Q
What is a principal axis on a lens?
A
A line that passes straight through the middle of a lens.
2
Q
What is the focal point of a lens?
A
Where the rays parallel to the principle axis meet.
3
Q
What is the focal length of a lens?
A
The distance between the middle of the lens and it’s focal point.
4
Q
How is focal length related to the power of a lens?
A
The more powerful a lens, the more strongly it converges parallel rays of light, so the shorter the focal length.
5
Q
What is the formula for the power of a lens in dioptres?
A
Power ( Dioptres ) = 1
———–
Focal length ( m )
