Question #928c3

1 Answer
Nov 21, 2017

It is a real, inverted image that is 1.5 times bigger than the object and forms on the side opposite to that of the object.

Explanation:

Thin Lens Equation: \qquad 1/u + 1/v = 1/f ...... (1)
u : is the object distance (always positive)
v : is the image distance (positive if the image forms on the opposite side as the object)
f : is the focal length of the lens (positive for a converging lens)

Given: \qquad u = +60 cm; \qquad f = +20 cm

Image Distance: Invert (1) to find the image distance v

v = (1/f-1/u)^{-1} = (1/(20 cm) - 1/(60 cm))^{-1} = +30 cm

Positive image distance indicates that the image is a real image and it forms on the side that is opposite to that of the object.

Magnification: \qquad m = -v/u = -(30cm)/(20cm) = -1.5

Negative sign for magnification indicates that the image is inverted. Its magnitude shows that the image is 1.5 times the size of the object.