A concave mirror of focal length 15 cm forms an image having twice linear dimensions of the object. The position of the object when the image is virtual will be

A concave mirror of focal length 15 cm forms an image having twice lin

1.	A concave mirror of focal length 15 cm forms an image having twice linear dimensions of the object. The position of the object when the image is virtual will be
Answer» 22.5 cm 7.5 cm 30 cm 45 cm Solution :For virtual IMAGE, m `= (-v)/(u) = + 2 or v = - 2u` `As (1)/(u) + (1)/(v) = (1)/(F)` `therefore(1)/(u)-(1)/(2u)=(1)/(-15)or(1)/(2u)=(1)/(-15)rArru=-7.5 cm`

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A concave mirror of focal length 15 cm forms an image having twice linear dimensions of the object. The position of the object when the image is virtual will be

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