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Tuesday, 07 April 2026
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An object of height 2.5cm is places 20cm from a convex mirror of focal length 10cm. ...

An object of height 2.5cm is places 20cm from a convex mirror of focal length 10cm. Calculate the height of its image.
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  • A 2.5 cm
  • B 3.0cm
  • C 5.0cm
  • D 25.0cm
Correct Answer: Option A
Explanation:
\(\frac{1}{v} = \frac{1}{f} - \frac{1}{u}\)
= \(\frac{1}{10} - \frac{1}{2} = \frac{1}{20}\)
v = 20
but h\(_i\) = \(\frac{v \times h_o}{u}\)
= \(\frac{20 \times 2.5 }{20}\)
= 2.5cm

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