Communication Systems Class 12 Notes Chapter 15 Topic 1 Communication 1. Communication Communication is the act of transmission and reception of information. 2. Communication System A system comprises of transmitter, communication channel and receiver. A block diagram of a generalised communication system is shown as below: 3. Transmitter It consists of transducer/signal generators, modulators and…
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Semiconductor Electronic: Material, Devices And Simple Circuits Class 12 Notes Class 12 Notes Chapter 14 1. Metals They possess very low resistivity or high conductivity. ρ ~ 10-2.10-8 Ωm, σ ~102. 108 Sm-1 2. Semiconductors They have resistivity or conductivity intermediate to metals and insulators. ρ ~ 10-5. 106 Ωm, σ ~ 10+5 .10-6 Sm-1 Types of…
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Nuclei Class 12 Notes Chapter 13 1. In every atom, the positive charge and mass are densely concentrated at the centre of the atom forming its nucleus. More than 99.9% mass of the atom is concentrated in the nucleus. 2. Atomic Mass Unit (amu) The unit to express atomic masses is called atomic mass unit.…
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Atoms Class 12 Notes Chapter 12 1. All elements consists of very small invisible particles, called atom. Every atom is a sphere of radius of the order of 10-10 m, in which entire mass is uniformly distributed and negative charged electrons revolve around the nucleus. 2. Experimental arrangement for α-scattering experiment and trajectory followed by α…
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Dual Nature of Radiation and Matter Class 12 Notes Chapter 11 1. Photoelectric Effect The phenomenon of emission of photoelectron from the surface of metal, when a light beam of suitable frequency is incident on it, is called photoelectric effect. The emitted electrons are called photoelectrons and the current so produced is called photoelectric current.…
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Wave Optics Class 12 Notes Chapter 10 1. Wave Optics Describes the connection between waves and rays of light. According to wave theory of light, light is a form of energy which travels through a medium in the form of transverse wave. 2. Wave front The locus of all those particles which are vibrating in…
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Ray Optics and Optical Instruments Class 12 Notes Chapter 9 1. Ray Optics or Geometrical Optics In this optics, the light is considered as a ray which travels in a straight line. It states that for each and every object, there is an image. 2. Reflection Reflection is the phenomenon of changing the path of…
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Electromagnetic Waves Class 12 Notes Chapter 8 1. Displacement Current The current which comes into play m the region in which the electric field and the electric flux is changing with time. It is given by 2. Need for Displacement Current Ampere’s circuital law for conduction current during charging of a capacitor was found inconsistent.…
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Alternating Current Class 12 Notes Chapter 7 1. Alternating Current (AC) It is the current which varies in both magnitude as well as direction alternatively and periodically. I = I0 sin ωt or I = I0 cosωt where, I0 = peak value or maximum value of AC. 2. Effective Value or rms Value of AC…
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Electromagnetic Induction Class 12 Notes Chapter 6 1. Magnetic Flux The magnetic flux linked with any surface is equal to total number of magnetic lines of force passing normally through it. It is a scalar quantity. 2. The phenomenon of generation of current or emf by changing the magnetic flux is known as Electromagnetic Induction…
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