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प्रश्न
Describe the positions of the source of light with respect to a concave mirror in Torch light.
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उत्तर
In a Torch, the light source is at the hub of a concave mirror, which gives you parallel light.
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संबंधित प्रश्न
Draw a ray diagram to show the path of the reflected ray corresponding to an incident ray of light parallel to the principal axis of a convex mirror and show the angle of incidence and angle of reflection on it.
State two positions in which a concave mirror produces a magnified image of a given object. List two differences between the two images.
Study the following diagram and select the correct statement about the device 'X' :
(A) Device 'X' is a concave mirror of radius of curvature 12 cm
(B) Device 'X' is a concave mirror of focal length 6 cm
(C) Device 'X' is a concave mirror of focal length 12 cm
(D) Device 'X' is a convex of mirror of focal length 12 cm
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.
A student wants to project the image of a candle flame on the walls of the school laboratory by using a mirror.
(a) Which type of mirror should he use and why?
(b) At what distance, in terms of focal length 'f' of the mirror, should he place the candle flame to get the magnified image on the wall?
(c) Draw a ray diagram to show the formation of the image in this case.
(d) Can he use this mirror to project a diminished image of the candle flame on the same wall? State 'how' if your answer is 'yes' and 'why not' if your answer is 'no.'
A spherical mirror produces an image of magnification -1.0 on a screen placed at a distance of 30 cm from the pole of the mirror.
(i) Write the type of mirror in this case.
(ii) What is the focal length of the mirror ?
(iii) What is the nature of the image formed ?
(iv) Draw the ray diagram to show the image formation in this case.
Name the mirror that can give an erect and enlarged image of an object.
Which type of mirror is used by a dentist?
Fill in the following blank with suitable word:
Parallel rays of light are reflected by a concave mirror to a point called the ..........
For what position of an object, a real and diminished image is formed by a concave mirror?
Draw the following diagram in your answer book and show the formation of image of the object AB with the help of suitable rays:
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.
Make labelled ray diagrams to illustrate the formation of:
a virtual image by a converging mirror.
Mark clearly the pole, focus, centre of curvature and position of object in each case.
Explain why, concave mirrors are used as shaving mirrors.
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
The image formed by a concave mirror is real, inverted and highly diminished (much smaller than the object). The object must be:
(a) between pole and focus
(b) at focus
(c) at the centre of curvature
(d) at infinity
Giving reasons, state the 'signs' (positive or negative) which can be given to the following:
(a) object distance (u) for a concave mirror or convex mirror
(b) image distance (v) for a concave mirror
(c) image distance (v) for a convex mirror
Describe the nature of image formed when the object is placed at a distance of 20 cm from a concave mirror of focal length 10 cm
An object 3 cm high is placed at a distance of 10 cm in front of a converging mirror of focal length 20 cm. Find the position, nature, and size of the image formed.
At what distance from a concave mirror of focal length 10 cm should an object be placed so that:
its virtual image is formed 20 cm from the mirror?
Name the mirror which can give:
an erect and enlarged image of an object.
Draw a ray diagram to show the formation of image of an object placed between the pole and focus of a concave mirror. State the position, size and nature of the image.
A student determines the focal length of a device 'X' by focusing the image of a distant object on a screen placed 20 cm from the device on the same side as the object. The device 'X' is
(a) Concave lens of focal length 10 cm
(b) Convex lens of focal length 20 cm
(c) Concave mirror of focal length 10 cm
(d) Concave mirror of focal length 20 cm
A student obtained a sharp image of the grills of a window on a screen using a concave mirror. His teacher remarked that for getting better results a well lit distant object (preferably the sun) should be focussed on the screen. What should be done for this purpose?
(A) Move the screen slightly away from the mirror
(B) Move the mirror slightly towards the screen
(C) Move the screen and the mirror away from the object
(D) Move the screen and the mirror towards the object
To construct ray diagram we use two light rays which are so chosen that it is easy to know their directions after reflection from the mirror. List these two rays and state the path of these rays after reflection. Use these rays to locate the image of an object placed between centre of curvature and focus of a concave mirror.
A student has to trace the path of a ray of light passing through a rectangular glass slab for four different values of angle of incidence.
(a) Write two important precautions for this experiment.
(b) List two conclusions the student will draw based on his experiment.
Choose the correct option from given alternative:
Consider the following properties of virtual images:
(A) cannot be projected on the screen
(B) are formed by both concave and convex lens
(C) are always erect
(D) are always inverted
Under which of the following conditions a concave mirror can form an image larger than the actual object?
The mirror having reflecting surface curved inwards ______.
An object at a distance of 30 cm from a
concave mirror gets its image at the same point. The focal length of the mirror is ______.
While looking at the above diagram, Nalini concluded the following.
- the image of the object will be a virtual one.
- the reflected ray will travel along the same path as the incident ray but in opposite direction.
- the image of the object will be inverted.
- this is a concave mirror and hence the focal length will be negative.
Which one of the above statements are correct?
Under which of the following conditions a concave mirror can form an image larger than the actual object?
The ENT doctor uses a ______.
In torches, searchlights, and headlights of vehicles, the bulb is placed ______ of the concave mirror.
What is a concave and convex mirror?
