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प्रश्न
According to cartesion sign convention, which mirror and which lens has negative focal length?
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उत्तर
Concave mirror is having a negative focal length.
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संबंधित प्रश्न
Draw ray diagrams to show the principal focus of a concave mirror.
Consider the following diagram in which M is a mirror and P is an object and Q is its magnified image formed by the mirror.
State the type of the mirror M and one characteristic property of the image Q.
If an object is at infinity (very large distance) in front of a concave mirror, where is the image formed?
With the help of a labelled ray diagram, describe how a converging mirror can be used to give an enlarged upright image of an object.
Explain why, concave mirrors are used as shaving mirrors.
According to the "New Cartesian Singh Convention" for mirrors, what sign has been given to the focal length of:
a concave mirror?
With the help of a labelled diagram, explain how a concave lens diverges a beam of parallel light rays. Mark the principal axis, optical centre, principal focus and focal length of the concave lens on the diagram.
Which of the following can make a parallel beam of light from a bulb falls on it?
(a) concave mirror as well as concave lens
(b) convex mirror as well as concave lens
(c) concave mirror as well as convex lens
(d) concave mirror as well as convex lens
Suppose you have three concave mirrors A, B and C of focal lengths 10 cm, 15 cm and 20 cm. For each concave mirror you perform the experiment of image formation for three values of object distance of 10 cm, 20 cm and 30 cm. Giving reason answer the following:
(a) For the three object distances, identify the mirror/mirrors which will form an image of magnification – 1.
(b) Out of the three mirrors identify the mirror which would be preferred to be used for shaving purposes/makeup.
(c) For the mirror B draw ray diagram for image formation for object distances 10 cm and 20 cm.
Beams of light are incident through the holes A and B and emerge out of box through the holes C and D respectively as shown in the figure. Which of the following could be inside the box?
