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A plane mirror of circular shape with ra...

A plane mirror of circular shape with radius `r=20cm` is fixed to the ceiling .A bulb is to be placed on the axis of the mirror.A circular area of radius `R=1m` on the floor is to be illuminated after reflection of light from the mirror. The height of the room is `3m` What is maximum distance from the center of the mirror and the bulb so that the required area is illuminated?

Text Solution

Verified by Experts

The correct Answer is:
75 cm
`DeltaABC ` & `DeltaAB'C`
`(x)/(0.20) = (x+3)/(1)`
x = 0.2x + 0.6`
`0.8x = 0.6 implies x = (3)/(4)` cm
x = 75 cm
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A plane mirror of circular shape with radius r=20cm is fixed to the ceiling .A bulb is to be placed on the axis of the mirror.A circular area fo radius R=1m on the floor is to be illuminated after reflection of fight from the mirror.Teh height of the room is 3m What is maximum distance fromt he center of the mirror and the bulb so that the required area is illuminated?

A concave mirror forms an image of 20 cm high object on a screen placed 5.0 m away from the mirror. The height of the image is 50 cm. Find the focal length of the mirror and the distance between the mirror and the object.

Knowledge Check

  • A toy car is placed at 15 cm in the front of the plane mirror. What is the distance of the image from the mirror?

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  • An object of height 0.5 m is placed in front of convex mirror. Distance of object from the mirror is equal to the focal length of the mirror. Height of the image of the object is

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