Advertisements
Advertisements
प्रश्न
Select the correct option:
A concave mirror is made by cutting a portion of a hollow glass sphere of radius 30 cm. The focal length of the concave mirror is:
पर्याय
24 cm
12 cm
15 cm
60 cm
Advertisements
उत्तर
15 cm
Explanation:
Radius of curvature = R = 30 cm
Focal length of concave mirror f = `"R"/2`
f = `30/2 = 15` cm
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.
What is a spherical mirror?
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.
A real and enlarged image can be obtained by using a
The radius of curvature of a convex mirror is 40 cm. Find its focal length.
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.
An object is placed at 4 cm distance in front of a concave mirror of radius of curvature 24 cm. Find the position of image. Is the image magnified?
Select the correct option:
A mirror forms a virtual image (diminished) of an object, whatever be the position of object:
Define the following term in relation to concave mirror.
Aperture
