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प्रश्न
Describe the positions of the source of light with respect to a concave mirror in Projector lamp.
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उत्तर
In a projector lamp, the light source is at the centre of the curvature of a concave mirror, which produces an image of the shape of the object itself.
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संबंधित प्रश्न
The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should the position of the object be relative to the mirror? Draw ray diagram to justify your answer.
A spherical mirror produces an image of magnification −1 on a screen placed at a distance of 40 cm from the mirror:
(i) Write the type of mirror.
(ii) What is the nature of the image formed?
(iii) How far is the object located from the mirror?
(iv) Draw the ray diagram to show the image formation in this case.
The radius of curvature of a spherical mirror is 20 cm. What is its focal length?
We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.
An object of size 7.0 cm is placed at 27 cm in front of a concave mirror of focal length 18 cm. At what distance from the mirror should a screen be placed, so that a sharp focused image can be obtained? Find the size and the nature of the image.
Find the focal length of a concave mirror whose radius of curvature is 32 cm.
Fill in the following blank with suitable word:
The focal length of a concave mirror is the distance from the ......... to the mirror.
For a convex mirror, parallel rays of light appear to diverge from a point called the ______.
For what position of an object, a real and diminished image is formed by a concave mirror?
Explain why, a ray of light passing through the centre of curvature of a concave mirror gets reflected back along the same path.
Which mirror is used as a torch reflector? Draw a labelled diagram to show how a torch reflector can be used to produce a parallel beam of light. Where is the bulb placed in relation to the torch reflector?
Which type of mirror is used in a solar furnace? Support your answer with reason.
The real image formed by a concave mirror is larger than the object when object is:
(a) at a distance equal to radius of curvature
(b) at a distance less than the focal length
(c) between focus and centre of curvature
(d) at a distance greater than radius of curvature
The real image formed by a concave mirror is smaller than the object if the object is:
(a) between centre of curvature and focus
(b) at a distance greater than radius of curvature
(c) at a distance equal to radius of curvature
(d) at a distance equal to focal length
An object is placed at the following distances from a concave mirror of focal length 15 cm, turn by turn:
(a) 35 cm
(b) 30 cm
(c) 20 cm
(d) 10 cm
Which position of the object will produce:
(i) a magnified real image?
(ii) a magnified virtual image?
(iii) a diminished real image?
(iv) an image of same size as the object?
According to the “New Cartesian Sign Convention” for mirrors, what sign has been given to the focal length of:
- a concave mirror?
- a convex mirror?
If an object of 10 cm height is placed at a distance of 36 cm from a concave mirror of focal length 12 cm, find the position, nature and height of the image.
When an object is placed at a distance of 15 cm from a concave mirror, its image is formed at 10 cm in front of the mirror. Calculate the focal length of the mirror.
An object is placed just outside the principal focus of concave mirror. Draw a ray diagram to show how the image is formed, and describe its size, position and nature.
An object is placed at a large distance in front of a concave mirror of radius of curvature 40 cm. The image will be formed in front of the mirror at a distance:
(a) 20 cm
(b) 30 cm
(c) 40 cm
(d) 50 cm
A concave mirror cannot be used as:
(a) a magnifying mirror
(b) a torch reflector
(c) a dentist's mirror
(d) a real view mirror
The mirror which can form a magnified image of an object is:
(a) convex mirror
(b) plane mirror
(c) concave mirror
(d) both convex and concave mirror
Why does a beam of light when it enters glass at an angle? Why does it not bend if it inters the glass at right angles?
Name the lens which can concentrate sun's rays to a point and burn a hole in a piece of paper.
In the following diagram. MM' is a concave mirror and AB is an object. Draw on your answer-sheet a ray diagram to show the formation of image of this object.
A student has focused the image of a candle flame on a white screen using a concave mirror. The situation is as given below:
Length of the flame = 1.5 cm
Distance of flame from the mirror = 18 cm
If the flame is perpendicular to the principal axis of the mirror, then calculate the following:
- Distance of the image from the mirror
- Length of the image
If the distance between the mirror and the flame is reduced to 10 cm, then what would be observed on the screen? Draw ray diagram to justify your answer for this situation.
Consider the following properties of virtual images:
- cannot be projected on the screen
- are formed by both concave and convex lens
- are always erect
- are always inverted
The correct properties are:
The mirror used by the ophthalmologist to examine the eye is _______.
The radius of curvature of a concave mirror whose focal length is 5cm is ______
Large ______ mirrors are used to concentrate sunlight to produce heat in solar furnaces.
In which of the following, the image of an object placed at infinity will be highly diminished and point sized?
The mirror having reflecting surface curved inwards ______.
For a real object, which of the following can produce a real image?
Which of the following mirror is used by a dentist to examine a small cavity in a patient’s teeth?
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?
What is a concave and convex mirror?
Write the uses of the concave mirror.
