Light reflection and refraction class 10 physics complete and short notes fully explained. Guarantee 95%+ marks

• Shaving mirrors.
• Vehicle headlights.
• Searchlights.
• Makeup mirrors.
• Microscopes.
• Telescopes.
• Solar cookers.
• Flashlights.

• When convex mirrors are used, the magnification of objects becomes simple.
• It is used in sunglasses.
• It is used as a rear-view mirror in automobiles.
• It’s utilised in ATMs and other places for security reasons.
• It’s used as a reflector for street lights.

Light reflection and refraction class 10 physics complete and short notes fully explained: Image Formation In Concave Mirrors:

1.Object at Infinity:

• Size of image – Highly diminished,
  point sized.
• Nature of image – Real and
  inverted

2. Object beyond C

• Size of image – Diminished
• Nature of image – Real and
  inverted

3. Object at C

• Size of image – Same size
• Nature of image – Real and
  inverted

4. Object between C & F

• Size of image – Enlarged
• Nature of image – Real and
  inverted

5. Object at F

• Size of image – Highly enlarged
• Nature of image – Real and
  inverted

6. Object between F and P

• Size of image – Enlarged
• Nature of image – Virtual and
  erect

Light reflection and refraction class 10 physics complete and short notes fully explained: Image Formation In Convex Mirrors:

1. Object at infinity

• Size of image – Highly diminished,
  point sized.
• Nature of image – Virtual and
  erect

2. Object at finite distance

• Size of image – Diminished
• Nature of image – Virtual and
  erect

Light reflection and refraction class 10 physics complete and short notes fully explained: Sign Convention In Mirrors:

Light reflection and refraction class 10 physics complete and short notes fully explained: Important Formulas:

1) Mirror formulae: 1/f= 1/v + 1/u

2) Magnification formula: m= height of image(h’)/height of object(h) = -v/u

Light reflection and refraction class 10 physics complete and short notes fully explained: Refraction of Light:

• Refraction of light is the change in the direction of a light ray passing from one medium to another.
• The bending of light ray is caused due to the differences in optical density between the two transparent media.

Light reflection and refraction class 10 physics complete and short notes fully explained: Laws of Refraction of Light:

• The incident ray refracted ray, and the normal to the interface of two media at the point of incidence all lie on the same plane.
• The ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant. This is also knowns as Snell’s law of refraction.

Light reflection and refraction class 10 physics complete and short notes fully explained: Rules of Refraction of Light:

1.Rarer to denser (Bends towards normal)

2.Denser to rarer (Bends away from normal)

Note: Refraction doesnot occur when light is incident normally or n light transits through media having same optical density.

Refraction through glass slab:

Light reflection and refraction class 10 physics complete and short notes fully explained: Refractive Index:

• The ratio of sine of angle of incidence to the sine of angle of refraction is a constant, for the light of a given colour and for the given pair of media.
• Absolute refractive index: If medium 1 is vacuum or air, the the refractive index of medium m is considered with respect to vacuum. This is called the absolute refractive index of the medium.

• Relative refractive index: The refractive index of medium 2 with respect to medium 1 is given by the ratio of the speed of light in medium 1 and the speed of light in medium 2.

Light reflection and refraction class 10 physics complete and short notes fully explained: Spherical Lenses:

1) Convex Lens:

2) Concave lens:

Note:

• A lens has two principal foci. They are represented by F1 and F2.
  
• The distance of the principal focus from the optical center of a lens is
  called its focal length.
  
• Thin Lenses: Lenses with an aperture much smaller than their radius
  of curvature.

Light reflection and refraction class 10 physics complete and short notes fully explained: Rules to obtain image through lens:

i. A ray of light from the object, parallel to the principal axis, after refraction from a convex lens, passes through the principal focus on the other side of the lens.

In case of a concave lens, the ray appears to diverge from the principal focus located on the same side of the lens.

ii. A ray of light passing through a principal focus, after refraction from a convex lens, will emerge parallel to the principal axis.

A ray of light appearing to meet at the principal focus of a concave lens, after refraction, will emerge parallel to the principal axis.

iii. A ray of light passing through the optical centre of a lens will emerge without any deviation.

• It is used as Hypermetropia i.e., to correct far-sightedness.
• It is used in microscopes, telescopes and magnifying glasses to subject all the light to a specific object.
• It is used in camera lenses because they focus light for a clear picture.