5A_U4_L17_Lenses

How is the vision of short-sighted people?

• They can see close things clearly but not things that are far away.

• They can see far-away things clearly but cannot concentrate the light from nearby things enough.

How is the vision of long-sighted people?

• They can see close things clearly but not things that are far away.

• They can see far things clearly but not things that are near.

A short sighted person can be helped by wearing...

• concave lenses.

• convex lenses.

• sunglasses.

A long-sighted person can be helped by wearing...

• a microscope.

• concave lenses.

• convex lenses.

TELESCOPES, MICROSCOPES and CAMERAS are...

• examples of medicines.

• examples of optical instruments.

• examples of opticians.

What can scientists do with optical instruments?

• Can see distant planets and stars.

• Can make music.

Optical instruments can make distant things appear closer and small things appear larger.

• TRUE

• FALSE

Which describes a convex lens?

• triangular in shape
• thicker on the edges than in the middle
• thicker in the middle than on the edges

Which describes a concave lens?

• more transparent in the middle
• thicker in the middle than on the edges

• thinner in the middle than on the edges

How does a concave lens differ from a convex lens?

• A convex lens is another way to describe a plane mirror; a concave lens is curved

• A concave lens is curved inward on both sides; a convex lens is on only one side

• A convex lens has a thick center and thin edges, a concave lens has a thin center and thicker edges

• A convex lens has a thin center and thick edges. a concave lens has a thick center and thinner edges