CBSE Class 10 Science Chapter 10 Light: Reflection and Refraction Notes
Introduction to Light – Reflection & Refraction
In Class 10 Science chapter 10 Light, the phenomena of reflection and refraction of light using the
straight-line propagation of light are taught to students. Furthermore, optical phenomena in nature is
examined. The reflection of light by spherical mirrors is discussed in the chapter so that their applications
are studied in real-life situations.
Light: Definition
Light is a form of energy that enables us to see things. Light starts from a source and bounces off objects
which are perceived by our eyes and our brain processes this signal, which eventually enables us to see.
Maxwell predicted that magnetic and electric fields travel in the form of waves and these waves move at the
speed of light. This led Maxwell to predict that light itself was carried by electromagnetic waves which
means that light is a form of electromagnetic radiation.
Nature of Light
Light behaves as a:
● ray, e.g. reflection
● wave, e.g. interference and diffraction
● particle, e.g. photoelectric effect
,According to the concept of wave-particle duality in quantum mechanics light exhibits both particle and
wave nature, depending upon the circumstances. Phenomena like diffraction, polarisation and interference
could be explained by considering light as a wave. The phenomenon of the photoelectric effect is explained
by assuming that light consists of particles called photons.
Laws of Reflection
Light incident on a surface separating two media
When light travels from one medium to another medium it either:
● gets absorbed (absorption)
● bounces back (reflection)
● passes through or bends (refraction)
When light is incident on a plane mirror, most of it gets reflected, and some of it gets absorbed in the
medium.
Characteristics of light
, ● Speed of light is given as c=λμ, where λ is its wavelength and μ is its frequency.
● Speed of light is a constant which is 2.998×108m/s or approximately 3.0×108m/s.
To know more about Properties of Light, visit here.
Reflection of light by other media
A medium that is polished well without any irregularities on its surface will cause regular reflection of light.
For example, a plane mirror. But even then some light gets absorbed by the surface.
Laws of Reflection
The incident ray, reflected ray and the normal all lie in the same plane. Angle of incidence = Angle of
reflection
[∠i=∠r]
To know more about the Law of Reflection, visit here.
Propagation of light
Rectilinear propagation of light: Light travels in a straight line between any two points.
Introduction to Light – Reflection & Refraction
In Class 10 Science chapter 10 Light, the phenomena of reflection and refraction of light using the
straight-line propagation of light are taught to students. Furthermore, optical phenomena in nature is
examined. The reflection of light by spherical mirrors is discussed in the chapter so that their applications
are studied in real-life situations.
Light: Definition
Light is a form of energy that enables us to see things. Light starts from a source and bounces off objects
which are perceived by our eyes and our brain processes this signal, which eventually enables us to see.
Maxwell predicted that magnetic and electric fields travel in the form of waves and these waves move at the
speed of light. This led Maxwell to predict that light itself was carried by electromagnetic waves which
means that light is a form of electromagnetic radiation.
Nature of Light
Light behaves as a:
● ray, e.g. reflection
● wave, e.g. interference and diffraction
● particle, e.g. photoelectric effect
,According to the concept of wave-particle duality in quantum mechanics light exhibits both particle and
wave nature, depending upon the circumstances. Phenomena like diffraction, polarisation and interference
could be explained by considering light as a wave. The phenomenon of the photoelectric effect is explained
by assuming that light consists of particles called photons.
Laws of Reflection
Light incident on a surface separating two media
When light travels from one medium to another medium it either:
● gets absorbed (absorption)
● bounces back (reflection)
● passes through or bends (refraction)
When light is incident on a plane mirror, most of it gets reflected, and some of it gets absorbed in the
medium.
Characteristics of light
, ● Speed of light is given as c=λμ, where λ is its wavelength and μ is its frequency.
● Speed of light is a constant which is 2.998×108m/s or approximately 3.0×108m/s.
To know more about Properties of Light, visit here.
Reflection of light by other media
A medium that is polished well without any irregularities on its surface will cause regular reflection of light.
For example, a plane mirror. But even then some light gets absorbed by the surface.
Laws of Reflection
The incident ray, reflected ray and the normal all lie in the same plane. Angle of incidence = Angle of
reflection
[∠i=∠r]
To know more about the Law of Reflection, visit here.
Propagation of light
Rectilinear propagation of light: Light travels in a straight line between any two points.
