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प्रश्न
Name the lens which can concentrate sun's rays to a point and burn a hole in a piece of paper.
उत्तर
A convex lens can concentrate the sun's rays to a point and burn a hole in a piece of paper.
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संबंधित प्रश्न
Draw a ray diagram for concave mirror when the object is between centre of curvature and focus.
The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should be the position of the object?
Name the type of mirror used in the following situation:
Headlights of a car
Support your answer with reason.
A 3 cm tall object is placed 18 cm in front of a concave mirror of focal length 12 cm. At what distance from the mirror should a screen be placed to see a sharp image of the object on the screen. Also calculate the height of the image formed.
In the concave reflector of a torch, the bulb is placed:
(a) between the pole and focus of reflector
(b) at the focus of reflector
(c) between focus and centre of curvature of reflector
(d) at the centre of curvature of reflector
An object is 100 mm in front of a concave mirror which produces an upright (erect image). The radius of curvature of the mirror is ______.
According to the "New Cartesian Singh Convention" for mirrors, what sign has been given to the focal length of:
a convex mirror?
The diagram shows a dish antenna which is used to receive television signals from a satellite. The antenna (signal detector) is fixed in front of the curved dish.
Figure
(a) What is the purpose of the dish?
(b) Should it be concave or convex?
(c) Where should the antenna be positioned to receive the strongest possible signals?
(d) Explain what change you would expect in the signals if a larger dish was used.
Study the following ray diagram and list two mistakes committed by the student while tracing it. Rectify these mistakes by drawing the correct ray diagram to show the real position and size of the image corresponding to the position of the object AB.
Under which of the following conditions a concave mirror can form an image larger than the actual object?
