A lens has a focal length of 0.1 m .Find the image distance when the object distance is
•A) 0.5 m
•B) 0.08 m
And write the type of the image

A) 0.125 m  (the image is real)

B) -0.4 m (the image is virtual)

Explanation:

For both situations we will use the Lens Equation:

(1)

Where:

is the focal length

is the distance between the object and the lens

is the distance between the image and the lens

Isolating :

(2)

Knowing this, let's begin with the answers:

A) When

The image is real

B) When

The negative sign indicates the image is virtual

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