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प्रश्न
An object of length 4 cm is placed in front of a concave mirror at distance 30 cm. The focal length of mirror is 15 cm.
- Where will the image form?
- What will be the length of image?
उत्तर
O = 4 cm
u = -30 cm
f = -15 cm
From mirror formula ,
`1/"f" = 1/"v" + 1/"u"`
∴ `1/"v" = 1/"f" - 1/"u"`
∴ `1/"v" = 1/(-15) - 1/(-30) = 1/30 - 1/15`
∴ `1/"v" = (-1)/30`
∴ v = -30 cm
Hence , the image is formed at a distance of 30 cm in front of the mirror .
m = `-"v"/"u" = "I"/"O"`
∴ I = `"-OV"/"u" = (-4 xx -30)/(-30) = -4`cm
Negative sign indicates inverted image.
So, I = 4 cm
Hence , the length of the image is 4 cm.
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संबंधित प्रश्न
Complete the following sentence:
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The diagram below in Figure, shows a convex mirror. C is its centre of curvature and F is its focus. (i) Draw two rays from A and hence locate the position of image of object OA. Label the image IB. (ii) State three characteristics of the image.
State the position of object for which the image formed by a concave mirror is of same size.
What type of mirror can be used to obtain a real image of an object?
Define the following term in relation to concave mirror.
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