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A 4 cm tall object placed at 20 cm gives an image at -40 cm (concave mirror). The image is:
A8 cm tall, real, inverted
B8 cm tall, virtual, erect
C4 cm tall, real, erect
D2 cm tall, virtual, inverted
Answer & Solution
Correct answer: A. 8 cm tall, real, inverted
1. m = -v/u = -(-40)/(-20) = -2.
2. h' = m × h = -2 × 4 cm = -8 cm.
3. Negative h' means inverted, real, and the size is 8 cm.
_Source: NCERT Class 10 Science, Ch 9 "Light Reflection and Refraction", §9.2.4_
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