Write the name. The imaginary line passing through two optical centres of lens - Science and Technology 1

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One Word Answer

Write the name.

The imaginary line passing through two optical centres of lens

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Solution

The imaginary line passing through two optical centres of lens- Principal axis

Concept: Lens
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Chapter 7: Lenses - Write the name

RELATED QUESTIONS

The power of a lens is - 5D.

1) Find its focal length.

2) Name the type of lens.


State the position of the object in front of a converging lens if It is used as a magnifying lens.


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Draw a ray diagram to show how a converging lens is used as a magnifying glass to observe a small object. Mark on your diagram the foci of the lens and the position of the eye.


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(ii) What is the size of the image I?
(iii)State two more characteristics of the image I.
(iv) Name the distance of the objects O from the optical centre of the lens.
(v) To what point will the rays return if the mirror is moved away from the lens by a distance equal to the focal length of the lens ?


State whether the given statement is true or false:
A concave lens is a converging lens.


Make the correct choices in the following items : 

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The instrument used to observe planets.

Aniket from Std. X uses spectacles. The power of the lenses in his spectacles is - 0.5 dioptre.
Answer the following questions:
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The point inside the lens on the principal axis through which light rays pass without changing their path is called _______.


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In the convex lens if an object is placed at 2 F1, the image is formed at ______.


The image formed by _______ lens is always virtual and small.


Write an Explanation.

Principal focus


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Write law in a given figure.


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Explain with a ray diagram the position, size, and nature of the various images formed by the convex lens.

An object beyond 2F1.


Explain with a ray diagram the position, size, and nature of the various images formed by a convex lens.

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Explain with a ray diagram the position, size, and nature of the various images formed by a convex lens.

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A concave lens can be used to produce an enlarged and erect image.


State whether the following statement is True or False

A convex lens always produces a real image.


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Distinguish between:

Concave lens and Convex Lens


Distinguish between:

Concave Lens and Convex Lens


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