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Class 10 Physics (India)

Course: Class 10 Physics (India) > Unit 1

Lesson 13: Lens formula & magnification
Science
Class 10 Physics (India)
Light – reflection & refraction
Lens formula & magnification
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Using the lens formula

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Problem

A real image forms 12, space, start text, c, m, end text from a convex lens when an object is kept 18, space, start text, c, m, end text from it.
What is the focal length, f, of the lens?
Note: Answer using the Cartesian sign convention.
f, equals
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3, slash, 5
  • a simplified improper fraction, like 7, slash, 4
  • a mixed number, like 1, space, 3, slash, 4
  • an exact decimal, like 0, point, 75
  • a multiple of pi, like 12, space, start text, p, i, end text or 2, slash, 3, space, start text, p, i, end text
start text, c, m, end text
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