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प्रश्न
Why do we prefer a convex mirror as a rear-view mirror in vehicles?
उत्तर १
We prefer a convex mirror as a rear-view mirror in vehicles because it gives a wider field of view, which allows the driver to see most of the traffic behind him. Convex mirrors always form a virtual, erect, and diminished image of the objects placed in front of it.
उत्तर २
A driver prefers to use a convex mirror as a rear-view mirror in his vehicle because this type of mirror has a wider field of view. Besides this, the convex mirror always forms virtual, erect and small sized images of the large number of objects at the same time.
संबंधित प्रश्न
An object is placed at a distance of 40 cm in front of a convex mirror of radius of curvature 40 cm. List four characteristics of the image formed by the mirror.
If the image formed by a mirror for all positions of the object placed in front of it is always diminished, erect and virtual, state the type of the mirror and also draw a ray diagram to justify your answer. Write one use such mirrors are put to and why.
A student obtains a blurred image of a distant object on a screen using a convex lens. To obtain a distinct image on the screen he should move the lens
(A) away from the screen
(B) towards the screen
(C) to a position very far away from the screen
(D) either towards or away from the screen depending upon the position of the object
A mirror forms an image which is 30 cm from an object and twice its height.
(a) Where must the mirror be situated?
(b) What is the radius of curvature?
(c) Is the mirror convex or concave?
State whether the following statement is true or false:
A diverging mirror is used as a rear-view mirror.
Fill in the following blank with a suitable word:
A ray of light which is parallel to the principal axis of a convex mirror, appears to be coming from ............ after reflection from the mirror.
Give two uses of a convex mirror. Explain why you would choose convex mirror for these uses.
The image formed by a spherical mirror is virtual. The mirror will be:
(a) concave
(b) convex
(c) either concave or convex
(d) metallic
Whatever be the position of the object, the image formed by a mirror is virtual, erect and smaller than the object. The mirror then must be:
(a) plane
(b) concave
(c) convex
(d) either concave or convex
An object 1 cm tall is placed 30 cm in front of a convex mirror of focal length 20 cm. Find the size and position of the image formed by the convex mirror.
An object is placed at the following distance from a convex lens of focal length 15 cm:
(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?
An object is placed at a distance of 100 cm from each of the above lenses A and B. Calculate (i) image distance, and (ii) magnification, in each of the two cases.
The angle formed between the normal and the refracted ray is known as the angle of incidence.
At the point of incidence, a line drawn at right angles to the surface, separating the two media, is called the normal.
To determine the focal length of a convex lens by obtaining a sharp image of a distant object we generally follow the following steps which are not in proper sequence.
(a) Hold the lens between the object and the screen
(B) Measure the distance between the lens and the screen
(C) Select a well lit distant object
(D) Place a screen opposite to the object on the lab table
(e) Adjust the position of the lens to form a sharp image
The correct sequence of these steps is:
(A) c, a, d, e, b
(B) c, d, a, e, b
(C) c, d, e, a, b
(D) c, a, e, d, b
Nature of the images formed by a convex mirror is _______.
Magnification produced by a rear view mirror fitted in vehicles
Identify the device used as a spherical mirror or lens in following case, when the image formed is virtual and erect in case.
Object is placed between infinity and device, image formed is diminished and between pole and focus, behind it.
What do you observe when an object is placed anywhere between P and infinity in front of a convex mirror?
Match the following.
| Column I | Column II |
| Convex mirror | Radio telescopes |
| Parabolic mirror | Rear-view mirror |
| Snell’s law | Kaleidoscope |
| Dispersion of light | sin i/sin r =μ |
| Refractive index | Rainbow |
