A converging lens has a focal length of 14.0cm. For an object to the left of the lens, at distances of 18.0cm and 7.00cm, determine: a. The image position
b. The magnification
c. Whether the image is real or virtual
d. Whether the image is upright or inverted

Explanation:

A converging lens id also known as a convex lens. A convex lens has a positive focal length.

Using the lens formula to determine the image distance from the lens for each object distance.

1/f = 1/u + 1/v

f = focal length

u = object distance

v = image distance

For an object placed at distance of 18.0cm with focal length 14.0cm,

1/v = 1/f-1/u

1/v = 1/14 - 1/18

1/v = 9-7/126

1/v = 2/126

v = 126/2

v = 63cm

Since the image distance is positive for an object 18cm from the lens, the image formed by the object at this distance is a real and inverted image.

The magnification = v/u = 63/18 = 3.5

Similarly for an object placed at distance of 7.0cm with focal length 14.0cm,

v = uf/u-f

v = 7(14)/7-14

v= -14.0 cm

Since the image distance is negative for an object placed 7.0 cm from the lens, the image formed by the object at this distance is a virtual and upright image.

The magnification = v/u = 14/7 = 2

Note that the negative value is not taken into account when calculating magnification. The negative value only tells us the nature of the image formed.

d) physical means can be used to separate the components of air.