An object with a height of 4.0 cm is placed 30.0 cm from a lens. the resulting inverted image has a height of 1.5 cm. what is the focal length of the lens? a. 15 cm b. 7.5 cm c 17 cm d. 8.2 cm e. 21 cm

Focal length of the lens is 8.2 cm.

Explanation:

It is given that,

Height of object, h = 4 cm

Object distance, u = -30 cm

Height of the image, h' = -1.5 cm (negative because the image is inverted)

We need to find the focal length of the lens. It can be calculated using lens formula as :

Magnification,

Image distance, v = 11.25 cm

f = 8.18 cm

or f = 8.2 cm

So, the focal length of the lens is 8.2 cm. Hence, this is the required solution.

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