Lenses

Question 1

What does a biconvex lens do?

Answer 1

Causes light rays that travel through it to CONVERGE (come together) to a precise point called the focal point of the lens.

Question 2

What does a biconcave lens do?

Answer 2

Causes light rays moving through it to DIVERGE (move apart)

Question 3

How can you determine the focal point of a divergent lens?

Answer 3

You must extend the refracted rays backwards until they meet.

Question 4

How is a focal point determined?

Answer 4

Finding it is determined experimentally by directing light rays through the lens.

Question 5

What types of substances does light travel through?

Answer 5

Transparent ans translucent substances

Question 6

Light can be bent in various ways depending on what? What does this impact?

Answer 6

The curvature and density of a lens.

This will directly impact the location of the focal point of a lens.

Question 7

For normal vision, where does the focal point of the lens fall?

Answer 7

On the retina

Question 8

What happens when the focal point does not fall on the retina?

Answer 8

It can be corrected by a lens (glasses, contacts)

Question 9

What does it mean when someone has myopia?

Answer 9

They are near sighted.
They can see close.
The focal point is in front of the retina
Their lens may be too thick
Their eyeball may be too long

Question 10

What does it mean when someone has hyperopia?

Answer 10

They are far sighted.
They can see far.
The focal point is in back of the retina
Their lens may be too thin
Their lens may be too short