Find radius of the curvature of the concave mirror having focal length 7.5 cm

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Question Id: PH0000002

Question: Find radius of the curvature of the concave mirror having focal length 7.5 cm.

To find: radius (r) of the curvature

Solution: 

we know the relation between focal length (f) and radius (r)  of curvature of mirror is

\[\Rightarrow f=\frac{r}{2}\]

\[\Rightarrow r=2 \times f\]

\[\Rightarrow r=2 \times 7.5\]
\[\Rightarrow r=15\]
∴ Hence radius of the curvature of the concave mirror is \(15cm\) .(Answer) 



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