A projection lantern is used to give the image of a slide on a screen. If the image is 24 times as large as the slide and the screen is 72.0m from the projecting lens, what is the position of the slide from the lens?
- 0.3m
-
3.0m
- 3.5m
- 4.0m
The correct answer is: B
Explanation
V = 72m
U = ?, Magnification = 24
But Magnification = V/U
∴ 24 = 72/U
U = 72/24
U = 3.0m
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