# An object 2 cm high is placed at a distance of 16 cm from a concave mirror, which produces 3 cm high inverted image. What is the focal length of the m

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An object 2 cm high is placed at a distance of 16 cm from a concave mirror, which produces 3 cm high inverted image. What is the focal length of the mirror? Also, find the position of the image.

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Correct Answer - -9.6cm, -24cm
Here, h_(1) = 2 cm, u = -16 cm, h_(2) = -3 cm
f = ? v = ?
As m = (h_(2))/(h_(1)) = -v/u, (-3)/2 = (-v)/(-16)
v = -24 cm
As (1)/(f) = (1)/(v) + 1/u, (1)/(f) = 1/(-24) - 1/16 = (-2-3)/28 = (-5)/48 or f = (-48)/5 = -9.6 cm.