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प्रश्न
In torches, search lights and headlights of vehicles the bulb is placed ______.
पर्याय
between the pole and the focus of the reflector
very near to the focus of the reflector
between the focus and centre of curvature of the reflector
at the centre of curvature of the reflector
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उत्तर
In torches, search lights and headlights of vehicles the bulb is placed very near to the focus of the reflector.
Explanation -
In torches, search lights and headlights of vehicles concave mirrors are used. When a light source is placed at the focus of the mirror, after reflection light rays become parallel to the principal axis. Due to this, the bulb is placed very near to the focus of the reflector.
संबंधित प्रश्न
A student obtains a sharp image of the distant window (W) of the school laboratory on the screen (S) using the given concave mirror (M) to determine its focal length. Which of the following distances should he measure to get the focal length of the mirror?

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What name is given to the distance between spherical mirror and carbon paper?
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(b) a virtual and enlarged image
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(d) a virtual and diminished image.
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(i) Pole
(ii) Centre of curvature
(iii) Radius of curvature
(iv) Principal axis
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Radius of curvature
The following figure shows a concave mirror with its pole (P), focus (F), and center of curvature (C). Draw a ray diagram to show the formation of the image of an object AB by the concave mirror.

Define the term Principle focus.
An object is placed in front of a concave mirror as shown in the following figure. By scale drawing, find the nature of the image. Given f = 10 cm, v = 30 cm.

