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Course: Optics (Essentials) - Class 12th > Unit 2

Lesson 4: How to calculate image and object distances and few more things!
Science
Optics (Essentials) - Class 12th
Why are objects closer in some mirrors than others?
How to calculate image and object distances and few more things!
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Using the magnification formula for mirrors

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Problem

As shown in the diagram below, an object O of height 3.0 cm is kept in front of a concave mirror, which forms the image I.
Find the height of the image hI.
Note: Let's write the answer in the Cartesian sign convention.
hI=
  • Your answer should be
  • an integer, like 6
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
  • an exact decimal, like 0.75
  • a multiple of pi, like 12 pi or 2/3 pi
cm