An object placed in front of a convex lens of focal length 10 cm produces an image at a distance of 15 cm from the lens and on the same side as the object.

An object placed in front of a convex lens of focal length 10 cm produces an image at a distance of 15 cm from the lens and on the same side as the object. Determine the position of the object.

Answers

f = 10 cm, v = -15 cm (same side), u = ?

$\frac{1}{f}$ = $\frac{1}{u}$ + $\frac{1}{v}$

$\frac{1}{u}$ = $\frac{1}{10}$ - $\frac{1}{-15}$

= $\frac{-3 - -2}{-30}$ = $\frac{1}{6}$

= 6 cm

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johnmulu answered the question on February 18, 2017 at 08:57

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