Mühendislik Ödevi Yardımı
Sahada çalışan ön saflardaki yapı mühendisleri için tasarlanan Mühendislik ödevi, tüm alanlardaki mühendislere çalışmalarında yardımcı olmayı umuyor.
Hesaplama sürecinin günlük işleyişinde hızlı bir şekilde veri üretebilmek için etkili olan çeşitli hesaplama yardımcılarını, hesaplama süreçlerini ve işletim yöntemlerini içerir. Kapsamlı hesaplama ve sorgulama fonksiyonlarıyla kullanıcılar, gerçek ihtiyaçlara göre ilgili operasyonel gereksinimleri arayabilir ve değerli mühendislik verileri üretebilir.
- Which one of the following is a way to focus your attention on driving so that you can recognize a hazard and understand the defense against it?Select your answer then click or tap Submit. Your driving profile Reasonable action The "What If?" Strategy
- 10.5 The transmission line sag depends upon A span length B tension in conductor C weight of the conductor per unit length D the amount of loads it supplies 10.6 An interconnection between two generating stations facilitates to A. keep their voltages constant B. Run them in parallel C. Transfer power in either direction D... Keep their current constant 10.7 The distribution for residential areas are: A. single phase B. three phase 3-wire C. three phase 4-wire D. non of the above 10.8 Surge absorbers protect against __ oscillation A. high voltage high frequency B. high voltage low frequency C. low voltage high frequency D. low voltage low frequency 10.9 Transmission line insulators are made of A. glass B. porcelain C. iron D. p.v.c
- 10.1 One of the disadvantages of the radial network is that when a fault occurs, it affects A the entire system B only the faulty part of the circuit c the faulty part before later extending to the entire system D the protective devices of the installation.
- W/m^2cdot K The air temperature is T_(infty )=20^circ C and the fin base temperature is T_(b)=10^circ C It is assumed that the temperature distribution in the fin is 1 -D along the X- direction and convection from the edges of the fin is neglected. For the solution, a uniform mesh (i.e ,h_(1)=h_(2)=h_(3)=h_(4)=L/4) of four linear elements is used. Questions: 1. Obtain an analytical solution for the temperature distribution in the fin and plot the temperature as a function of position. 2. Calculate the rate of heat transfer to the fin. 3. Determine the fin efficiency. 4. The fin has a density of rho =3000kg/m^3 and is mounted on a base material with a thickness th_(b)=2mm and density rho b=8000kg/m^3 . The half-width of the gap between adjacent fins is th_(g)=2mm . Therefore, the volume of the base material associated with each fin is th_(b)W_(b)(th+2th_(g)) 5. Determine the ratio of the absolute value of the rate of heat transfer to the fin to the total mass of material (fin and base material associated with the fin). 6. Prepare a contour plot that shows the ratio of the heat transfer to the fin to the total mass of material as a function of the fin length L and fin thickness thth. 7. What is the optimal value of L and thth that maximizes the absolute value of the heat transfer rate to the mass of material?
- Exercice 1: Savoirs essentiels 15 points 10 points 1. Donner les formules chimiques des composés sulvants: dioxyde de carbone, ion hydronium. (1pt) 2. Définir indicateur coloré. (0,5pt) 3. Donner deux étapes du raffinage du pétrole. (1pt) 4. Donner deux modes de production de l'énergie électrique au Cameroun. 5. On donne la formule suivante : P=UI (1pt) Donner la signification des grandeurs physiques qui interviennent dans cette formule.(0,75pt) 6. Donner le rôle de la bougie dans un moteur à combustion interne. (0,75pt) Exercice 2: Application des savoirs et savoir-faire/5 points 1. Mise en solution d'un solide ionique/1,5 point On dissout 15 g de chlorure de sodium NaCl dans de l'eau. 1.1. Ecrire l'équation de dissolution du chlorure de sodium dans l'eau. (0,75 pt) 1.2. Déterminer la masse molaire de NaCl. (0,25 pt) 1.3. Déterminer la quantité de matière de NaCl. (0,5p t) Données: Masses molaires en grammes par mole: Na=23;Cl=35,5 2. Utilisation du pH/0,5 point On donne les solutions suivantes : solution S_(1)(pH=3) solution S2(pH=7,5) Classe ces solutions par ordre d'acidité croissante. (0,5pt) 3. Matières plastiques/o ,5 point Décrire un test d'identification du polyéthylène PE. (0,5pt) 4. Système poulies-courroie 1 point La roue menante A d'un système poulies-courroie a un diamètre D_(A)=40cm et fait 250 tr en 15 s. Le diamètre de la roue menée B est D_(B)=20cm 4.1. Déterminer la vitesse de rotation N_(A) de la roue A. (0,5pt) 4.2. Déterminer la vitesse de rotation N_(B) de la roue menée. (0,5pt) 5. Schéma développée d'une Installation /1 point Réaliser le schéma développé d'une installation électrique constituée de: Une lampe en simple allumage; Une prise de courant; Un fusible de protection. 6. Moteur à quatre temps / 0,5 point Un moteur à quatre temps constitué d'un seul cylindre tourne à une vitesse de 2000tr/min Déterminer le nombre de cycles par minute. (0,5pt) Decision