Advertisements
Advertisements
प्रश्न
The image formed by a convex mirror is of size one third the size of object. How are u and v related?
Advertisements
उत्तर
Magnification is
m = `"I"/"O" = (1/3"O")/"O" = 1/3`
A convex mirror always forms a virtual and an upright image. So,
m = `-"v"/"u"`
∴ `-"v"/"u"` = `1/3`
∴ v = `-1/3"u"`
But , u is always negative
∴ v = `1/3"u"`
∴ u = 3v
APPEARS IN
संबंधित प्रश्न
One half of a convex lens of focal length 10 cm is covered with a black paper. Can such a lens produce an image of a complete object placed at a distance of 30 cm from the lens? Draw a ray diagram to justify your answer. A 4 cm tall object is placed perpendicular to its principal axis of a convex lens of focal length 20 cm. The distance of the object from the lens is 15 cm. Find the nature, position and the size of the image.
A 4 cm tall object is placed on the principal axis of a convex lens. The distance of the object from the optical centre of the lens is 12 cm and its sharp image is formed at a distance of 24 cm from it on a screen on the other side of the lens. If the object is now moved a little away from the lens, in which way (towards the lens or away from the lens) will he have to move the screen to get a sharp image of the object on it again? How will the magnification of the image be affected?
A ray of light is incident normally on a plane mirror. What will be the:
- angle of incidence?
- angle of reflection?
Name the two types of spherical mirrors. What type of mirror is represented by the:
- back side of a shining steel spoon?
- front side of a shining steel spoon?
A concave lens produces an image 20 cm from the lens of an object placed 30 cm from the lens. The focal length of the lens is:
(a) 50 cm
(b) 40 cm
(c) 60 cm
(d) 30 cm
Define the terms focus and focal length of a concave mirror. Draw diagram to illustrate your answer.
Draw a ray diagram to show the formation of image of an object kept in front of a convex mirror. State three characteristics of the image.
A real and enlarged image can be obtained by using a
A concave mirror forms a real image of an object placed in front of it at a distance 30 cm, of size three times the size of object. Find
- the focal length of mirror
- position of image.
Complete the following diagrams shown in the below figure by drawing the reflected ray for each incident ray.
