Light (10)

Reflection; Spherical Mirrors - Concave and Convex; Mirror Formula and Magnification; Refraction - Glass Slab, Refractive Index; Spherical Lenses;  Lens Formula and Magnification; Power of a Lens

The power of a lens is +4D. Find the focal length of this lens

The power of a lens is +4D. Find the focal length of this lens. An object is placed at a distance of 50 cm from the optical centre of this lens.

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An object of height 10 cm is placed 25 cm away

An object of height 10 cm is placed 25 cm away from the optical centre of a converging lens of focal length 15 cm. Calculate the image-distance

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The ability of a medium to refract light is expressed in terms of its optical density

The ability of a medium to refract light is expressed in terms of its optical density. Optical density has a definite connotation. It is not the

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Define the following terms in the context of a diverging mirror

Define the following terms in the context of a diverging mirror :

  1. Principal
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To get an enlarged, real and inverted image of an object

To get an enlarged, real and inverted image of an object by a concave mirror, where should the object be placed ? Draw a labelled ray diagram to

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The absolute refractive index of Ruby is 1.7

The absolute refractive index of Ruby is 1.7. Find the speed of light in Ruby. The speed of light in vacuum is 3 x 108 m/s.

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Name the type of mirror which facilitates

Name the type of mirror which facilitates

  1. Shaving,
  2. Observing large images of the
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Is the type of lens used converging or diverging

Study the ray diagram given below and answer the questions that follow:

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Define pole of a spherical mirror

Define pole of a spherical mirror

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A 4 cm tall object is placed on the principal axis of a convex lens

 A 4 cm tall object is placed on the principal axis of a convex lens. The distance of the object from the optical centre of the lens is 12 cm and

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A student traces the path of a ray of light through a triangular glass prism for different values of angle of incidence

A student traces the path of a ray of light through a triangular glass prism for different values of angle of incidence. On analysing the ray

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A student traces the path of a ray of light through a rectangular glass slab for the different values of angle of incidence

A student traces the path of a ray of light through a rectangular glass slab for the different values of angle of incidence. He observes all

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A student used a device (X) to obtain/focus the image of a well illuminated distant building on a screen

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.

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A student obtains a sharp image of the distant window (W) of the school laboratory on the screen (S) using the given concave mirror

A student obtains a sharp image of the distant window (W) of the school laboratory on the screen (S) using the given concave mirror (M) to

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One half of a convex lens of focal length 10 cm is covered with a black paper

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

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What is meant by power of a lens ? Define its S.I. unit.

What is meant by power of a lens ? Define its S.I. unit.

You have two lenses A and B of focal lengths +10 cm and -10 cm respectively.

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What is meant by scattering of light

What is meant by scattering of light ? Use this phenomenon to explain why the clear sky appears blue or the sun appears reddish at sunrise.

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If the image formed by a mirror for all positions of the object placed in front of it is always erect and diminished

If the image formed by a mirror for all positions of the object placed in front of it is always erect and diminished, what type of mirror is it ?

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The absolute refractive indices of glass and water are 4/3 and 3/2 respectively

The absolute refractive indices of glass and water are 4/3 and 3/2 respectively. If the speed of light in glass is 2 x 108 m/s,

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Why does the sun appear reddish early in the morning

Why does the sun appear reddish early in the morning ? Will this phenomenon be observed by an astronaut on the Moon ? Give reason to justify your

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Why do stars twinkle ? Explain

 Why do stars twinkle ? Explain.

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What is meant by power of a lens ? Write its SI unit

What is meant by power of a lens ? Write its SI unit. A student uses a lens of focal length 40 cm and another of -20 cm. Write the nature and

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State the laws of refraction of light. Explain the term absolute refractive index of a medium

State the laws of refraction of light. Explain the term ‘absolute refractive index of a medium’ and write an expression to relate it with the

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If the image formed by a spherical mirror for all positions of the object placed in front of it is always erect and diminished

If the image formed by a spherical mirror for all positions of the object placed in front of it is always erect and diminished, what type of

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A student traces the path of a ray of light through a glass prism

A student traces the path of a ray of light through a glass prism as shown in the diagram, but leaves it incomplete and unlabelled. Redraw and

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Draw the path of a ray of light when it enters one of the faces of a glass

Draw the path of a ray of light when it enters one of the faces of a glass slab at an angle of nearly  45°. Label on it (i) angle of refraction,

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A 10 cm tall object is placed perpendicular to the principal axis

 A 10 cm tall object is placed perpendicular to the principal axis of a convex lens of focal length 12 cm. The distance of the object from the

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A student holding a mirror in his hand, directed the reflecting surface of the mirror

A student holding a mirror in his hand, directed the reflecting surface of the mirror towards the Sun. He then directed the reflected light on to

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