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प्रश्न
Choose the correct alternative and rewrite the following:
Mirror used by a dental surgeon is ..........................
विकल्प
plane
convex
concave
convex and concave
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उत्तर
concave
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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).
Find out the letters of English alphabet or any other language known to you in which the image formed in a plane mirror appears exactly like the letter itself. Discuss your findings.
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?
When a spherical mirror is held towards the sun and its sharp image is formed on a piece of carbon paper for some time, a hole is burnt in the carbon paper.
- What is the nature of spherical mirror?
- Why is a hole burnt in the carbon paper?
- At which point of the spherical mirror the carbon paper is placed?
- What name is given to the distance between spherical mirror and carbon paper?
- What is the advantage of using a carbon paper rather than a white paper?
A diverging lens is used in:
(a) a magnifying glass
(b) a car to see objects on rear side
(c) spectacles for the correction of short sight
(d) a simple camera
- A small object is placed 150 mm away from a diverging lens of focal length 100 mm.
- Copy the figure below and draw rays to show how an image is formed by the lens.
- Calculate the distance of the image from the lens by using the lens formula.
- Copy the figure below and draw rays to show how an image is formed by the lens.
- 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 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
State the direction of incident ray which after reflection from a spherical mirror gets reflected along its own path. Give a reason.
Define the following terms in the context of spherical mirrors :
(i) Pole
(ii) Centre of curvature
(iii) Radius of curvature
(iv) Principal axis
The radius of curvature of a convex mirror is 40 cm. Find its focal length.
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.
Define the term Aperture.
Define linear magnification produced by a mirror?
If the focal length of a spherical mirror is 10 cm, what is the value of its radius of curvature?
The radius of curvature of a spherical mirror is 18 cm. What is the focal length of this mirror?
The distance from the center of curvature of the mirror to the pole is called the focal length of the mirror.
