Question 1
A plane convex lens is made of glass (n = 1.5) with one flat surface and the other having a radius of 20 cm. What is the focal length (in cm) of the lens?
◦
20
◦
30
◦
40
◦
10
◦
50
Question 2
A telescope is constructed with two lenses separated by a distance of 25 cm. The focal length of the objective is 20 cm. The focal length of the eyepiece is 5 cm. Calculate the magnitude of the angular magnification of the telescope.
◦
6
◦
4
◦
8
◦
10
◦
5