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Question
When an object is placed at a distance of 50 cm from a concave spherical mirror, the magnification produced is, `-1/2`. Where should the object be placed to get a magnification of, `-1/5`?
Solution
Given,
Magnification `(m)=-1/2`
Therefore, using the magnification formula, we get
Now,
Magnification = `m=-1/5`
Therefore, using the mirror formula, we get
`1/f=1/-"mu"+1/u`
`or -3/50=(-5)/-5+1/u`
`or (-3)/50=5/u+1/u`
`or (-3)/50 =6/4`
`u=-50xx6/3=-100` cm
The object should be placed in front of the mirror at a distance of 100 cm to get the magnefiction of `-1/5`
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