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प्रश्न
Rays from Sun converge at a point 15 cm in front of a concave mirror. Where should an object be placed so that size of its image is equal to the size of the object?
विकल्प
15 cm in front of the mirror
30 cm in front of the mirror
between 15 cm and 30 cm in front of the mirror
more than 30 cm in front of the mirror
उत्तर
30 cm in front of the mirror
Explanation -
The rays from the sun are considered parallel to the principal axis. These rays will converge at the focus of the concave mirror. It shows that focal length of the mirror is 15 cm and the centre of curvature is 30 cm. In case of concave mirror, when the object is placed at the centre of curvature, the image is formed at the centre of curvature itself and of the same size.
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संबंधित प्रश्न
A ray of light is incident on a plane mirror making an angle of 90° with the mirror surface. The angle of reflection for this ray of light will be:
(a) 45°
(b) 90°
(c) 0°
(d) 60°
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(C) no image as the screen has been removed
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