Electromagnetic Spectrum Notes PDF

Quarter 2 - Module 1: Electromagnetic Spectrum  MELC compare the relative wavelengths of different forms of electromagnetic waves (S10FE-IIa-b-47)  describe the electrical and 1 magnetic field property of a wave; At the end of...

Quarter 2 - Module 1: Electromagnetic Spectrum  MELC compare the relative wavelengths of different forms of electromagnetic waves (S10FE-IIa-b-47)  describe the electrical and 1 magnetic field property of a wave; At the end of the relate period, frequency, lesson, you 2 and wavelength of a wave; should be able to:  calculate the period of a 3 wave; and At the end of the discuss the wave lesson, you 4 properties of electromagnetic waves. should be able to: ELECTROMAGNETIC WAVES ✘ In 1865, Scotsman James Clerk Maxwell (1831-1879) formulated his electromagnetic theory, predicting that visible light is electric and magnetic phenomena. ELECTROMAGNETIC WAVES ✘ The third and fourth equations of the famous Maxwell’s equations encompasses the Faraday’s law of induction and Ampere’s law which respectively assumed that a changing magnetic field induces an electric field and that a changing electric field generates a magnetic field. ELECTROMAGNETIC WAVES ✘ According to Maxwell, an electromagnetic wave is an electrical and magnetic disturbances produced by accelerated charges, such as vibrating electrons, that propagates through empty space at the speed of light, c = 3.0 x 10⁸ m/s. Features of Electromagnetic Waves Positive Charge Negative Charge ✘ Electric field is defined as the electric force per unit charge. ✘ The direction of the field is taken to be the direction of the force it would exert on a positive test charge. ✘ The electric field is radially outward from a positive charge and radially in toward a negative point charge. Features of Electromagnetic Waves The magnetic field is the area around a magnet in which the effect of magnetism is felt. REPEL Features of Electromagnetic Waves MAGNETIC FIELD ✘ As these waves are produced by a changing electric field E and a changing magnetic field B, they have an electric and a magnetic component where each component is perpendicular to the other. ✘ Since both components are perpendicular to the direction of the wave motion, all electromagnetic waves are transverse. The electric and magnetic fields in a electromagnetic wave. ELECTROMAGNETIC WAVES ✘ Electromagnetic (EM) waves are also known as Hertzian waves as German ✘ Heinrich R. Hertz (1857-1894) verified the predictions of Maxwell. Features of Electromagnetic Waves Maxwell calculated the speed of electromagnetic waves to be 3.0 Material Speed x108 m/s in an empty space and (km/s) is denoted as the constant, c. Vacuum 300,000 Electromagnetic waves travel Air