A screen is placed 80cm from an object. A lens is used to produce on the screen an image with a magnification of 3. What...

A screen is placed 80cm from an object. A lens is used to produce on the screen an image with a magnification of 3. What is the distance between the object and the lens? Calculate the focal length of that lens.

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M=3
u+v=80cm
v/(80-v)=3
(80-v)*3=v
240-3v=v
240=4v
v=60cm
u=80-60=20cm
1/f=1/60+1/20=1/15
f=15cm

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Alambi answered the question on January 21, 2019 at 06:54

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