D. Linear element of the circuit is such one whose characteristic is a straight line.

SULEYMAN DEMIREL UNIVERSITY

ENGINEERING FACULTY

 

BASIC CIRCUIT THEORY

TEST QUESTIONS with SOLUTIONS

COMPILER Mrs. L. Kiziyeva

 

 

Almaty

ББК

К

 

Утверждено и рекомендовано Ученым Советом Университета имени Сулеймана Демиреля, протокол № 1 от 01.09.2005

 

Автор Кизиева Лариса Александровна

 

К Кизиева Л.А. Теория линейных электрических цепей. (Образцы тестовых заданий с решениями). Алматы, 2006-56с.

 

ISBN

 

 

ББК

 

К

 

ISBN ã Кизиева Л.А. 2006

ã Университет имени

Сулеймана Демиреля, 2006

PREFACE

 

 

Basic Circuit Theory is the first subject of hardware cycle at the university. In some sense the subject is a collection of knowledge of the parts of Physics such as electricity and magnetism and the higher Maths, but it is not a mechanical combination of the knowledge. These topics’ mutual penetration allows us to consider electromagnetic phenomena from a new point of view, on the basis of their practical application. This is a mixture of previous knowledge on a new level, of higher quality, with a set of specific methods of problems’ solution. The specificity of the subject is to represent the real phenomena as a model of electrical circuit with definite set of properties. As a rule, students have a lot of difficulties with the subject because they cannot consolidate immediately their theoretical knowledge and transform it into practice. This book allows students to understand the general approach to standard problems’ solution. There is a set of theoretical questions with explanation what is correct and why in the book. Problems’ solutions request presence of consolidated knowledge. The sequence of problems is defined by accidental way to enforce the students to consider all questions in process of searching tasks concerning to definite topic. Such a way the students have got ability of involuntary keeping in mind of information. We take the principle to forestall consideration of topics by students themselves to cause and support their interest to the subject. Searching the questions, which are connected with a definite theme, students consider another questions by the way and to repeat previous themes. It allows them to be ready for quizzes, tests, and other check steps any time.

 

Compiler

1. What statement is correct?

A. Electric energy is measured by watts.

B. An electrical circuit is an interconnection of electrical devices.

C. When current and voltage have the same algebraic signs, the device is delivering power.

D. Voltage is a measure of the rate at which energy is being transferred.

E. Unit of charge is ampere.

 

Solution:

A – wrong. Electric energy is measured in Joules (J); watt (W) is a unit of power.

B – correct.

C – wrong. Under passive sign convention, the current reference arrow is directed toward the terminal with the positive voltage reference mark. Under this convention, the device power is positive when it absorbs power and is negative when it delivers power.

When current and voltage have the same algebraic signs, p will be positive, so the device will absorb power.

D – wrong. Voltage is a measure of the energy required to move a small charge from one point to another. Power is a measure of the rate at which energy is being transferred.

E – wrong. Unit of charge is Coulomb (C). Unit of current is Ampere (A).

Answer: B.

 

2. What statement is wrong?

A. The reference marks are only benchmarks assigned at the beginning of the analysis.

B. Current is a through variable, but voltage is an across variable.

C. One-port network has got two terminals.

D. Linear element of the circuit is such one whose characteristic is a straight line.

E. Battery is considered as voltage source.

 

Solution:

D – wrong. Linear means that the defining characteristic is a straight line through the origin. Elements whose characteristics do not pass through the origin (even if it’s a straight line) or are not a straight line are said to be nonlinear.