Chapter-8|Electromagnetic Waves|NCERT 12th Physics: Uses of Electromagnetic Waves: Uses of electromagnetic waves are as follows 1.Radio Wave:- (I) These waves are used in in amplitude modulation(AM). (II) These are used in frequency modulation(FM) (III) These are used in cell phones (IV) These are used in television broadcasting(TV) 2.Microwave:- (I) These are used in cooking purpose […]
Chapter-8|Electromagnetic Waves|NCERT 12th Physics: Electromagnetic Spectrum: The the orderly arrangement of electromagnetic wave in increasing or decreasing order of wavelength (λ) or frequency(υ) is called electromagnetic spectrum. It consist of following waves. 1. Radio waves 2. Microwaves 3. Infrared waves. 4. Visible or light rays. 5. Ultraviolet rays. 6. X-rays 7. Gamma(γ) rays.
Chapter-8|Electromagnetic Waves|NCERT 12th Physics: Characteristics of Electromagnetic Waves: 1. Electromagnetic waves are produced by accelerated charge. 2. These waves do not required any material medium for propagation. 3. It travel with the speed of light. 4. Electromagnetic waves are transverse in nature. 5. The energy in electromagnetic waves is divided on an average, equally between
Chapter-8|Electromagnetic Waves|NCERT 12th Physics: Electromagnetic Waves: Electromagnetic waves are the waves which are produced due to change in electric field E and magnetic field B Sinusoidally and propagating through space such that the two fields are perpendicular to each other and perpendicular to the direction of wave propagation. Source of Electromagnetic Waves: An oscillating charge
Chapter-8|Electromagnetic Waves|NCERT 12th Physics: Maxwell’s Equations: Maxwell’s equations are the basic laws of electric city and Magnetism. All the basic principles of electromagnetism can be explained in terms of four fundamental equations call maxwell’s equations. Maxwell did not discovered four equations, but he worked on them and stated that these four fundamental equations define complete
Chapter-8|Electromagnetic Waves|NCERT 12th Physics: Displacement Current: Ampere’s circuital law state that the line integral of magnetic field B, around any closed path is equal to μ₀ times the total current threading the closed path i.e According to Maxwell the above equation is logically inconsistent. With the help of following observation he prove it. Maxwell’s Experiment to Prove
Chapter-7|Alternating Current |NCERT 12th Physics: Wattless Current: The current which consumes no power for its maintenance in the circuit is called wattless current of idle current. Or The current in AC circuit is said to be wattless if the average power consumed in the circuit is zero. The average power of a given circuit is
Chapter-7|Alternating Current |NCERT 12th Physics: Transformer: It is a device which is used to increase or decrease the alternating voltage. The Transformer are two types (I) Step-Up transformer – Increase voltage (II) Step-down transformer – Decrease voltage Construction: It consists of large number of laminated soft iron cores. There are two types of winding one
Chapter-7|Alternating Current |NCERT 12th Physics: Energy Stored in an Inductor: When in inductor(L), current(I) is applied, the magnetic flux will be developed.
Chapter-7|Alternating Current |NCERT 12th Physics: L-C Oscillations: When a capacitor is supplied with AC current, it gets charged When this charged capacitor is connected with an inductor, current flows through inductor, giving rise to magnetic flux. Hence, induced EMF is produced in this circuit. Due to this, the charge of the capacitor decreases and an
