Class 10 physics
Chapter 1: Light – Reflection and Refraction
1. Introduction to Light
Definition:
• Light is a form of energy that enables us to see objects.
• It travels in a straight line and exhibits both wave-like and particle-like properties.
Nature of Light:
• Behaves as both a wave and a particle (wave-particle duality).
• Exhibits properties like reflection, refraction, and dispersion.
2. Reflection of Light
a. Laws of Reflection
1. The angle of incidence (i) is equal to the angle of reflection (r).
2. The incident ray, reflected ray, and normal all lie in the same plane.
b. Types of Reflection
• Regular Reflection:
• Occurs on smooth surfaces.
• Reflected rays are parallel, forming a clear image.
• Diffuse Reflection:
• Occurs on rough surfaces.
• Reflected rays scatter in different directions, no clear image forms.
c. Image Formation by Plane Mirrors
Characteristics of the Image:
• Virtual and erect
• Same size as the object
• Laterally inverted (left-right reversal)
, • Image distance behind the mirror = Object distance in front
3. Spherical Mirrors
a. Types of Spherical Mirrors
• Concave Mirror: Reflecting surface curved inward.
• Convex Mirror: Reflecting surface curved outward.
b. Important Terms in Spherical Mirrors
Term Definition
Pole (P) Center of the mirror’s surface
Centre of Curvature (C) Center of the sphere from which the mirror is a part
Radius of Curvature
Distance between the Pole and Centre of Curvature
(R)
Principal Axis Imaginary line passing through C and P
Point where parallel rays converge (concave) or appear to diverge
Principal Focus (F)
(convex)
Focal Length (f) Distance between the Pole and the Focus (f = R/2)
c. Mirror Formula & Magnification
Mirror Formula:
Where:
• f = Focal length
• v = Image distance
• u = Object distance
Magnification Formula:
Where:
• m = Magnification
• h' = Height of image
• h = Height of object
• v = Image distance
• u = Object distance
Chapter 1: Light – Reflection and Refraction
1. Introduction to Light
Definition:
• Light is a form of energy that enables us to see objects.
• It travels in a straight line and exhibits both wave-like and particle-like properties.
Nature of Light:
• Behaves as both a wave and a particle (wave-particle duality).
• Exhibits properties like reflection, refraction, and dispersion.
2. Reflection of Light
a. Laws of Reflection
1. The angle of incidence (i) is equal to the angle of reflection (r).
2. The incident ray, reflected ray, and normal all lie in the same plane.
b. Types of Reflection
• Regular Reflection:
• Occurs on smooth surfaces.
• Reflected rays are parallel, forming a clear image.
• Diffuse Reflection:
• Occurs on rough surfaces.
• Reflected rays scatter in different directions, no clear image forms.
c. Image Formation by Plane Mirrors
Characteristics of the Image:
• Virtual and erect
• Same size as the object
• Laterally inverted (left-right reversal)
, • Image distance behind the mirror = Object distance in front
3. Spherical Mirrors
a. Types of Spherical Mirrors
• Concave Mirror: Reflecting surface curved inward.
• Convex Mirror: Reflecting surface curved outward.
b. Important Terms in Spherical Mirrors
Term Definition
Pole (P) Center of the mirror’s surface
Centre of Curvature (C) Center of the sphere from which the mirror is a part
Radius of Curvature
Distance between the Pole and Centre of Curvature
(R)
Principal Axis Imaginary line passing through C and P
Point where parallel rays converge (concave) or appear to diverge
Principal Focus (F)
(convex)
Focal Length (f) Distance between the Pole and the Focus (f = R/2)
c. Mirror Formula & Magnification
Mirror Formula:
Where:
• f = Focal length
• v = Image distance
• u = Object distance
Magnification Formula:
Where:
• m = Magnification
• h' = Height of image
• h = Height of object
• v = Image distance
• u = Object distance
