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Question
An object is placed at a distance of 10 cm from a convex mirror of focal length 5 cm.
(a) Draw a ray-diagram showing the formation image
(b) State two characteristics of the image formed
(c) Calculate the distance of the image from mirror.
Solution
(a) Ray Diagram-
(b) Following are the characteristics of the image formed:
(2) It is smaller than the object.
(c) Distance of the object 'u' = -10 cm
Focal length of the convex mirror is 5 cm.
We have to find the distance of the image 'v'.
Using the mirror formula, we get
`1/f=1/v+1/u`
⇒`1/5=1/v+1/-10`
⇒`1/5=1/v-1/10`
⇒`1/5+1/10=1/v`
⇒`2/10+1/10=1/v`
⇒`1/v=3/10`
⇒`v=10/3` ⇒`v=3.3 cm `
Thus, the distance of the image is 3.3 cm behind the mirror.
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