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प्रश्न
An object is 24 cm away from a concave mirror and its image is 16 cm from the mirror. Find the focal length and radius of curvature of the mirror, and the magnification of the image.
उत्तर
Distance of object (u) = -24 cm
Distance of image (v) = -16 cm
We have to find the focal length of the mirror (f) and the magnification of the image (m).
Using the mirror formula, we get
`1/f=1/u+1/v`
`1/f=1/-24+1/-16`
`or 1/f=(-2-3)/48`
`or 1/f=(-5)/48`
`or f=-48/5`
`f=-9.6` cm
Therefore, the focal length of the concave mirrio is 9.6
R adius of curvature (R)=2f
`R=2xx-9.6`
`R=-19.2 cm`
Therefore, the radius of curvature of the mirror is 19.2 cm
Now, using the magnification formula, we get
`m =(-v)/u`
`m=(-16)/-24`
m=0.66
Thus, the image is real, inverted and small in size.
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