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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).
विकल्प
This device is a concave lens of focal length 8 cm.
This device is a convex mirror of focal length 8 cm.
This device is a convex lens of focal length 4 cm.
This device is a convex lens of focal length 8 cm.
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उत्तर
This device is a convex lens of focal length 8 cm.
Explanation:
The incident rays after passing through the lens converge at the focus. So, the device 'X' is a converging or a convex lens. The distance between the lens and the screen gives the focal length of the lens.
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संबंधित प्रश्न
Explain the following term related to spherical lenses:- principal axis
Name the spherical mirror which has:
(a) virtual principal focus.
(b) real principal focus.
What is a spherical mirror?
The radius of curvature of a convex mirror is 40 cm. Find its focal length.
In the following figure shows a concave mirror with its pole (P), focus (F) and centre of curvature (C). Draw a ray diagram to show the formation of the image of an object AB by the concave mirror.
Define the term Principle focus.
A concave mirror can be used to produce a parallel beam of light. Draw a ray to illustrate this.
Spherical mirrors are one form of ______ mirrors.
What is the difference between virtual images of an object formed by a concave mirror and a convex mirror?
Define the following terms in the context of a diverging mirror:
- Principal focus
- Focal length
Draw a labelled ray diagram to illustrate your answer.
