Step1-answers-juan Corrales Suaza.docx

UNIT 1 – ELECTRODYNAMIC AND WAVES

TUTOR: OMAR LEONARDO LEYTON

STUDENT: JUAN CORRALES CANO CODE: 203058 GROUP: 38

UNIVERSIDAD ABIERTA Y A DISTANCIA UNAD ESCUELA DE CIENCIAS BÁSICAS, TECNOLOGÍA E INGENIERÍA INGENIERIA DE TELECOMUNICACIONES TEORIA ELECTROMAGNETICA Y ONDAS

MEDELLIN, 09 DE MARZO DE 2019 STEP 1

Answer to the questions 1. Explain the concept of "loss tangent" applied to electromagnetic wave propagation media and indicate how it is calculated. ANSWER: The tangent of losses or tangent delta is a measure of the state of an insulation. It is also called the dissipation factor and is a measure of the dielectric losses of a solid or liquid insulator. Therefore, its magnitude depends on the type of insulation and its conditions and is independent of its volume. From the point of view of wave propagation, the characteristic behavior of a medium depends not only on the parameters J, ∈ μ but also on the operating frequency. The formula for loss tangent is: 𝑡𝑎𝑛𝜃 =

𝐽 𝜔∈

2. According to the "tangent of losses", how can the means of propagation be classified? ANSWER: The means of propagation are classified as: • Perfect Dielectrics • Perfect drivers • Good Insulators • Good Drivers • Dissipative Dielectrics 3. What concept does each of the means of propagation defined in the previous point have? ANSWER: • Perfect Dielectrics: The conduction current is not present, there are no losses. • Perfect Conductors: It does not present the polarization current, so it has no capacitive effects or load accumulation. • Good Insulators: They present conduction current and have losses by JOULE effect; but this effect is almost negligible compared to the capacitive effect. It is also called "low loss dielectrics" • Good Conductors: Presents the polarization current, therefore the capacitive effects, but it is the conduction current and the losses given by the Joule effect • Dissipative Dielectrics: They have both effects and none is negligible compared to the other.

4. What does the propagation speed of an electromagnetic wave depend on? ANSWER: The speed or dynamics of propagation of the wave depends on the characteristics of the medium in which the propagation takes place and not on the characteristics of the wave or the force that generates it. 𝒄 → 𝑆𝑝𝑒𝑒𝑑 𝑜𝑓 𝑙𝑖𝑔ℎ𝑡 𝑖𝑛 𝑡ℎ𝑒 𝑣𝑎𝑐𝑢𝑢𝑚 𝑟𝑒𝑓𝑟𝑎𝑐𝑡𝑖𝑣𝑒 𝑖𝑛𝑑𝑒𝑥 ← 𝒏 = 𝒗 → 𝑆𝑝𝑒𝑒𝑑 𝑜𝑓 𝑙𝑖𝑔ℎ𝑡 𝑖𝑛 𝑡ℎ𝑒 𝑚𝑖𝑑𝑑𝑙𝑒

5. What is the penetration depth of an electromagnetic wave in a medium and how can I calculate it? ANSWER: The depth of penetration (δ) is a parameter that depends on both the characteristics of the material and the wave that passes through it. This is calculated as: 𝛿=

1

𝑓: 𝑊𝑎𝑣𝑒 𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 √𝜋𝑓𝜇𝐽 𝜇: 𝑚𝑎𝑔𝑛𝑒𝑡𝑖𝑐 𝑝𝑒𝑟𝑚𝑒𝑎𝑏𝑖𝑙𝑖𝑡𝑦 𝐽: 𝐶𝑜𝑛𝑑𝑢𝑐𝑡𝑖𝑣𝑖𝑡𝑦

In addition, δ is a measure of the degree of penetration of an electromagnetic wave in the medium.