Advertisements
Advertisements
प्रश्न
When a spherical mirror is held towards the sun and its sharp image is formed on a piece of a carbon paper for some time, a hole is burnt in the carbon paper.
What name is given to the distance between spherical mirror and carbon paper?
Advertisements
उत्तर
The distance between the mirror and the carbon paper is the focal length.
APPEARS IN
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:- centres of curvature
Give one use each of a concave and a convex mirror.
What is the name of the phenomenon in which the right side of an object appears to be the left side of the image in a plane mirror?
The diverging lens in part (a) is replaced by a converging lens also of focal length 100 mm. The object remains in the same position and an image is formed by the converging lens. Compare two properties of this image with those of the image formed by the diverging lens in part (a).
A ray of light travels from a denser medium to a rarer medium. How will it bend?
What do you understand by the focus and focal length of a spherical mirror? Show them on the separate diagrams for each of a concave mirror and a convex mirror.
AB and CD, two spherical mirrors, from parts of a hollow spherical ball with its centre at O as shown in the diagram. If arc AB = `1/2` arc CD, what is the ratio of their focal lengths? State which of the two mirrors will always form virtual image of an object placed in front of it and why.
How is the focal length of a spherical mirror related to its radius of curvature?
How will you distinguish between a plane mirror, a concave mirror and a convex mirror, without touching them?
The magnification for a mirror is -3. How are u and v related?
A straight stick partly dipped in water obliquely appears to be bent at the surface of the water.
Draw a ray diagram in each of the following cases to show the formation of image, when the object is placed :
(i) between the optical centre and principal focus of a convex lens.
(ii) anywhere in front of a concave lens.
(iii) at 2F of a convex lens.
State the signs and values of magnifications in the above-mentioned cases (i) and (ii).
Define the term principal focus in case of convex mirror. Draw a convex mirror and show its principal focus and focal length clearly.
Complete the following diagrams shown in the following figures by drawing the reflected rays.
Define the term Focus of a concave mirror.
The diagram below shows the parallel rays incident on a convex mirror. C is the centre of the curvature of the mirror. By drawing the paths of the reflected rays, label the focus F and hence find the focal length of the mirror.
The image formed in a plane mirror is always inverted.
