Thin lenses and optical instruments

Question 1 of 10

In the human eye, focusing on objects at different distances is done by

Question 2 of 10

An object is placed 30 cm from a converging lens of focal length 10 cm. Find the image distance.

Question 3 of 10

An object 2 cm tall is 40 cm from a converging lens of focal length 10 cm. Find the height of the image.

Question 4 of 10

A diverging lens has a positive power.

Question 5 of 10

Draw ray diagrams to show image formation by a converging lens when the object is (a) between F and 2F, (b) between the lens and F. Give one use for each arrangement.

Question 6 of 10

A converging lens of focal length 10 cm has a power of ___ dioptres.

Question 7 of 10

An astronomical telescope in normal adjustment has its lenses separated by

Question 8 of 10

An object is placed 20 cm from a converging lens of focal length 15 cm. Find the image distance.

Question 9 of 10

Compare the human eye with a camera under the headings: focusing, control of light, image receiver and nature of image.

Question 10 of 10

A magnifying glass uses a diverging lens.