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Question
The photograph of a house occupies an area of 1.75 cm2on a 35 mm slide. The slide is projected on to a screen, and the area of the house on the screen is 1.55 m2. What is the linear magnification of the projector-screen arrangement?
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Solution
Area of the house on the slide = 1.75 cm2
Area of the image of the house formed on the screen = 1.55 × 104 cm2
Arial magnification, ma =` "Area of image"/"Area of object" = (1.55 xx 10^4)/1.75 `
= 8857.14
∴ Linear magnifications, `m_l = sqrtm_a`
=`sqrt(8857.14)` = 94.11
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