Electrical Engineering Answers

Find the impulse response h[n] for a causal LTI discrete-time systems satisfying the given difference equations and indicate whether the system is a FIR or an IIR system.

y[n] - 1/2 * y * [n - 2] = 2x * [n] - x[n - 2]

1.Find the Laplace Transform of the function g(t)=u(t)+2exp(-2t)u(t)+2cos(3000t)u(t)+

exp(-5t)sin(5000t)u(t) . Indicate the positions of zeros and poles .

2.) Find the Inverse Transform of the function 1/(s^2+6s+9)

Consider the circuit shown in Fig. 1. If 𝑉1 = 10V; the BJT has a β = 200 and 𝐼𝑠 = 10 𝑎𝐴 and the

capacitors are short circuits in the frequency range of operation, determine the values of 𝑅1 and 𝑅2, if

the amplifier is to have a gain of 100. What is its’ operating point ? It is given that 𝑅3 = 100 Ω.

A 120Vrms 60Hz source supplies four loads connected in parallel as shown

below

Load 1: 150 kVA, at 0.8 pf leading

Load 2: 100 kVA, at unity pf

Load 3: 200 kVA, at 0.6pf lagging

Load 4: 80kW and 95kVAR (inductive)

Find

a) Power Factor

b) Calculate the value of capacitance/inductance connected in parallel

that will raise the power factor to unity

The airbag igniter is modeled by the following circuit. Determine the time it

takes the voltage across the igniter to reach its first peak after switching

from A to B 𝑅 =3Ω,𝐶 = 1

30𝐹 and 𝐿=60𝑚𝐻

Q1- Consider a continuous time signal x(t)=2cos(21πt+30)+5cos(18 πt)

a) What is the signal frequency and What is the Nyquist rate of the signal?

b) Write a MATLAB M function or a script called sampley4p1 to perform

sampling:

1- Compare the results when the sampling frequencies of 10Hz , and 30 Hz were

used for the time between zero and 0.2sec?

2- determine the sampling frequency which result in the problem of aliasing .2-

Q2- a) suppose that the resulting samples from the Q1 (part a) passed through a 4

bits A/D convertor,

write a MATLAB code to perform the quantization, your MATLAB code and the

report should result in a figure contain the samples and the quantized values in the

same figure for comparison.

Students Tasks for the project1

6

Note: The project materials will be completed at the end of

lecture 4 after interdicting the interpolation technique

mid band gain of common CE amplifier

1. The largest distance to use MMSIF is………

a. 2 Km.

b. 1.5 Km.

c. 5 Km.

d. 1 Km.

2. ……. uses for moderate distance and moderate data rate.

a. SMSIF.

b. MMSIF.

c. MMGIF.

d. Both (b) and (c) .

3. The ray path in SMSIF is…...

a. TIR.

b. Axial ray.

c. Oscillatory Fashion.

d. Both (a) and (b).

4. …….wavelength is used with MMGIF.

a. 850 nm.

b. 1310 nm.

c. 1550 nm.

d. Both (a) and (b).

5. ……...has the minimum attenuation from other configurations of fiber optics.

a. MMSIF. b. MMGIF.

c. SMSIF. d. Both (a) and (b).

What will the value of the answer variable be after the code segment below has been run.

int answer = 11;  

int  number60 = 18, number97 = 6;  

answer += number60 * number97;  

Solve the following circuit on paper and validate the solution on MultiSim. Circuit Diagram: Task 1: Workout the value of current ‘Io’ in the circuit. (On paper)