1997 B5

An object is placed 30 mm in front of a lens. An image of the object is located 90 mm behind the lens.

(a) Is the lens converging or diverging? Explain your reasoning.

(b) What is the focal length of the lens?

(c) On the axis below, draw the lens at position x = 0. Draw at least two rays and locate the image to show the situation described above.

(d) Based on your diagram in (c), describe the image by answering the following questions in the blank spaces provided.

Is the image real or virtual? __________

Is the image smaller than, larger than, or same size as the object? __________

Is the image inverted or upright compared to the object? __________

(e) The lens is replaced by a concave mirror of focal length 20 mm. On the axis below, draw the mirror at position x = 0 so that a real image is formed. Draw at least two rays and locate the image to show this situation.