NCERT Class 10 Science — Chapter 1: Light - Reflection and Refraction

When two thin lenses are placed in contact, the net power of the combination is equal to:

A lens is defined as a transparent material bounded by which of the following surfaces?

Assertion (A): The power of a convex lens is positive. Reason (R): A convex lens has a positive focal length, and power is defined as the reciprocal of focal length.

For a spherical mirror with a small aperture, what is the relationship between the radius of curvature (R) and the focal length (f)?

With reference to images formed by a concave mirror, consider the following statements: 1. An object placed beyond the centre of curvature (C) gives a diminished, real, inverted image between the principal focus (F) and C. 2. An object placed at the centre of curvature (C) forms an image at the principal focus (F). 3. An object placed between C and F gives an enlarged, real, inverted image beyond C. Which of the statements given above is/are correct?

Which type of mirror is most suitable for viewing the full-length image of a tall, distant building using a small surface area?

Assertion (A): Rays parallel to the principal axis of a convex mirror converge to a point in front of the mirror. Reason (R): The principal focus of a convex mirror is located behind the mirror.

Where does the centre of curvature of a convex mirror lie relative to the reflecting surface?

With reference to the image formed by a plane mirror, consider the following statements: 1. It is virtual and erect. 2. It is vertically inverted. 3. It is always larger than the object. Which of the statements given above is/are correct?

Which one of the following materials possesses the highest refractive index?

In which of the following media does light travel with the highest speed?

Which one of the following is the SI unit of the power of a lens?

When an object is placed at the centre of curvature (C) of a concave mirror, the image formed is:

Where is the image formed by a concave mirror when the object is located at infinity?

What is the nature of the image formed by a concave lens, regardless of the object's position?

What is the nature of the image formed by a plane mirror?

What is the approximate refractive index of water?

What is the nature of the image formed by a concave mirror when the object is placed between the pole (P) and the principal focus (F)?

Match List I with List II and select the correct answer using the code given below the lists: List I (Term) | List II (Description) A. Centre of curvature | 1. Straight line passing through the pole and the centre of curvature B. Principal axis | 2. Point on the principal axis where parallel rays intersect C. Principal focus | 3. Distance between the pole and the principal focus D. Focal length | 4. Centre of the hollow sphere of which the mirror is a part

Consider the following statements about diffraction: 1. In such a case, the straight-line treatment of light rays remains strictly valid. 2. When an opaque object on the path of light becomes very small, bending of light can occur around it. Which of the statements given above is/are correct?

Under which condition does a concave mirror produce a virtual and erect image?

With reference to the laws of refraction, consider the following statements: 1. The incident ray and the refracted ray lie in different planes relative to the normal at the point of incidence. 2. For a given colour of light and a given pair of media, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant. Which of the statements given above is/are correct?

Which one of the following represents the correct mirror formula relating object distance (u), image distance (v), and focal length (f)?

Which one of the following expressions represents the magnification (m) produced by a lens in terms of object distance (u) and image distance (v)?

Where is the image formed by a convex lens when the object is placed at its principal focus (F)?

Consider the following statements with respect to spherical mirrors: 1. The pole of the mirror lies at the centre of curvature. 2. The principal axis is normal to the mirror at its pole. Which of the statements given above is/are correct?

What happens to a ray of light passing through the optical centre of a thin lens?

Match List I with List II and select the correct answer using the code given below the lists: List I (Device) | List II (Function/Property) A. Headlight of a car | 1. Used to produce a powerful parallel beam of light B. Dentist’s mirror | 2. Used to see a large image of teeth C. Solar furnace | 3. Used to concentrate sunlight to produce heat D. Rear-view mirror | 4. Used to get a wider field of view

Which type of mirror is commonly used in vehicle headlights to produce a powerful parallel beam of light?

Assertion (A): When a light ray enters a glass slab from air, it bends towards the normal. Reason (R): The speed of light is higher in glass than in air.

Which one of the following equations correctly defines the absolute refractive index (n) of a medium?

In the case of a concave mirror, where is the image formed if the object is placed at the principal focus?