Question

image distance, v=−18cm

magnification, m=−51​ as the image formed is real hence it will be inverted.

We know, 

m=−uv​⟹−51​=−(u−18​)⟹u=−(5×18)=−90cm

Applying the lens formula,

f1​=v1​+u1​⟹f1​=−181​+−901​⟹f1​=90−5−1​⟹f=−15cm

Since focal length is negative, therefore it is a concave mirror.

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Answer 1

Answer:

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Explanation:

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