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Question
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.
Solution
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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What would your image look like if you stood close to a large:
concave mirror?
If the radius of curvature of a concave mirror is 20 cm, its focal length is:
In which of the following, the image of an object placed at infinity will be highly diminished and point sized?
