Light And Optics - SS1 Physics Past Questions and Answers - page 2

The dual nature of light refers to its ability to exhibit characteristics of both waves and particles. As a wave, light exhibits properties such as interference, diffraction, and polarization. It can be described by its wavelength, frequency, and amplitude. On the other hand, light also behaves as a particle known as a photon. Photons carry energy and momentum and can interact with matter in a particle-like manner. This dual nature is explained by quantum theory and is fundamental to our understanding of light.

Reflection is the phenomenon in which light bounces off a surface. Reflection occurs when the incoming light strikes the surface and is redirected back into the same medium. The angle of incidence, which is the angle between the incident light and the surface normal, is equal to the angle of reflection, which is the angle between the reflected light and the surface normal. This relationship is described by the law of reflection. Reflection plays a crucial role in vision, mirrors, and the behaviour of light in various optical systems.

The laws of reflection state that the angle of incidence is equal to the angle of reflection. When light rays strike a smooth plane mirror, they are reflected back in a manner that follows these laws. The angle of incidence is measured between the incident ray and the normal, while the angle of reflection is measured between the reflected ray and the normal. Both angles are measured from the perpendicular line (normal) drawn to the surface of the mirror. These laws ensure that the reflected rays maintain the same angle of incidence as the incident rays.

Plane mirrors form virtual images. When an object is placed in front of a plane mirror, an image is formed behind the mirror. The image formed is virtual, meaning it cannot be projected onto a screen. It is formed by the apparent intersection of the reflected rays, giving the illusion of an image. The image formed is upright, meaning it has the same orientation as the object. The image formed in a plane mirror is also of the same size as the object, maintaining a one-to-one correspondence.