Advertisements
Advertisements
प्रश्न
What is a virtual image?
What are virtual images?
Advertisements
उत्तर
When the rays of light reflecting from an object appear to meet in a virtual form, then the images formed in this way are called virtual images.
संबंधित प्रश्न
A student used a device (X) to obtain/focus the image of a well illuminated distant building on a screen (S) as shown below in the diagram. Select the correct statement about the device (X).
Explain the following term related to spherical lenses:- optical centre
A ray of light is incident normally on a plane mirror. What will be the:
- angle of incidence?
- angle of reflection?
A ray of light is incident normally on a plane mirror. What will be the
angle of reflection?
Name the two types of spherical mirrors. What type of mirror is represented by the:
front side of a shining steel spoon?
A 50 cm tall object is at a very large distance from a diverging lens. A virtual, erect and diminished image of the object is formed at a distance of 20 cm in front of the lens. How much is the focal length of the lens?
What do you mean by the term dispersion?
State the direction of incident ray which after reflection from a spherical mirror gets reflected along its own path. Give a reason.
State the kind of mirror used
(a) by a dentist, and
(b) as a street light reflector.
State the types of mirrors used for (i) headlights and (ii) rear view mirror, in cars and motorcycles. Give to justify your answer in each case.
State the two convenient rays that are chosen to construct the image by a spherical mirror for a given object? Explain your answer with the help of suitable ray diagrams.
How is the focal length of a spherical mirror related to its radius of curvature?
A concave mirror forms a virtual image of size twice that of the object placed at a distance 5 cm from it. Find:
- the focal length of the mirror
- position of image
An object 5 cm high is placed at a distance 60 cm in front of a concave mirror of focal length 10 cm. Find the position and size of the image.
Select the correct option:
Which mirror is used in periscope?
Define the following term in relation to concave mirror.
Radius of curvature
What do you understand by the term real image?
What is a mirror formula?
Find the height of the image of a body of height 1.5m in a mirror with a magnification of 1.5.
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.
A concave mirror can be used to produce a parallel beam of light. Draw a ray to illustrate this.
An object 10 cm high is placed at a distance of 20 cm in front of a spherical mirror of focal length 25 cm. By scale drawing find the nature, position, and magnification of the image in the following case:
Convex mirror
The following Figure shows a concave mirror MM' on which a ray of light incident from a point P gets reflected to meet the principle axis at O.
(a) Find, by construction, the position of the centre of curvature of the concave mirror.
(b) Write down the value for the radius of curvature of the mirror.
(c) Calculate the focal length of the mirror.
(d ) Which relation is used in deducing the focal length from the radius of curvature?
The spherical mirror used in a beauty parlour as make-up mirror is _______.
Assertion: Incident ray is directed towards the centre of curvature of spherical mirror. After reflection it retraces its path.
Reason: Angle of incidence (i) = Angle of reflection (r) = 0°
A student traces the path of a ray of light passing through a rectangular slab.
 |
 |
 |
 |
For measuring the angle of incidence, he must position the protractor in the manner shown in the figure:
Name the type of mirror used in the following situation:
Solar furnace
Support your answer with reason.
A ray of light is incident towards a plane mirror at an angle of 30° with the mirror surface. What will be the angle of reflection?
Define the following terms in the context of a diverging mirror:
- Principal focus
- Focal length
Draw a labelled ray diagram to illustrate your answer.
