# Search results

1. ### Generating Ricean Channel using MATLAB

Homework Statement I want to generate a Ricean channel using MATLAB Homework Equations Assuming that Ω = -30 dB. The Attempt at a Solution I know how to generate a Rayleigh channel using matlab: H = 1/sqrt(2) * ( randn(N,M) + j*randn(N,M) ) But I really have no idea how to do that for...
2. ### Simulating an OFDM channel

Hi everyone, I'm trying to simulate an OFDM following a few steps, and I'm stuck at the first: The first step: You have a channel with independent zero mean complex Gaussian taps along with exponentially decaying power profile E{|hk|2|}=e-k/3 with k ∈ [0,21] First of all, does this notation...
3. ### Reduce T-Network Feedback Resistance

Thank you for your quick respond. My question is whether this approach OK or not. And if the feedback resistance can be reduced more.
4. ### Reduce T-Network Feedback Resistance

Homework Statement Reduce the feedback resistance for the following T-Network Homework Equations Basic circuit analysis (Thevenin maybe?) The Attempt at a Solution My first though was to use Thevenin, and actually I've found some book used that method:
5. ### Multiple Diodes Problem

Thanks. I really appreciate your help. :)
6. ### Multiple Diodes Problem

Sorry for the "typo" ^^" Anyway, this is what I've done: http://s32.postimg.org/da0hvrf5h/004.jpg Am I doing OK?
7. ### Multiple Diodes Problem

Homework Statement If V(1)=10 V and V(0)=5 V, and the voltage threshold for all diodes is 0.6 V. Determine the current through every diode and the output voltage Vo if V1=V4= 5V and V2=V3=10 V. Homework Equations Basic KCL & KVL. The Attempt at a Solution I know that the basic idea to...
8. ### Mutual Inductance Transfer function

Homework Statement Find Io(s)/Ii(s) Homework Equations Basic KVL laws. The Attempt at a Solution My idea is to start from the RHS of the circuit until I get a relation between Io(s) and Ii(s). Actually I stopped at this point, I wondered whether my approach is appropriate or not since...
9. ### Deriving transfer function of ramp response out of a plot

Homework Statement The first order ramp unit response is shown in the graph below. Determine: 1. The transfer function. 2. Plot the error function e(t) then determine its maximum magnitude and the time http://s24.postimg.org/cdbhqm80j/Capture.png Homework Equations G(s)=(1/T)/(S+1/T) ... G(s)...
10. ### Electromagnetics: Moving loop in a static magnetic field

Homework Statement A conducting square loop (L × L) moving with velocity vo ay m/s where the magnetic flux density is B=Bo ax Wb/m2 in 0 < y < 2L, and is equal to zero when 0 > y and y > L. Determine the current in the loop and plot its magnitude as a function in the loop's position in the...
11. ### Tank problem

That's the exact statement of the problem. I guess we have to assume that the tank is full of water, which means that the volume of water is 1 m3.
12. ### Otto cycle engine

Homework Statement An Engine works within Otto cycle where the compression ratio is 6, and 350 kJ of heat was added to it. Determine the efficiency of the cycle and the work done if Cp/Cv is 1.45 Homework Equations Efficiency Otto = (1- r1-k) Efficiency (eff.) =Work (W) /Heat Transferred (Q)...
13. ### Tank problem

Homework Statement A tank has a saturated liquid at 0.2 MPa. An amount of heat is transferred until the pressure in the tank became 0.1 MPa. If the volume of the tank 1 m3. Determine: 1- The final state of the water 2- The mass of the vapor in the tank 3- The work 4- The process on P-v...
14. ### Thermodynamics: Air compressor

Homework Statement Air enters a compressor at 100 kPa and 290 K, where it is compressed adiabatically, where the flow rate is 0.1 kg/s. If the volume compression ratio is (V1/V2=8). Determine the following (Assuming the air is ideal with constant specific heat): 1- The temperature and the...
15. ### Thermodynamics: Polytropic Process

Homework Statement Q1- 0.15 kg of air (Ideal) compressed in a polytropic process (PV1.5=C) from 0.06 m3 to 0.01 m3. If the initial pressure was 0.25 MPa. Determine: 1- The initial temperature and the final pressure. 2- The work done during the process. Homework Equations P1 V1 = m R T P1...
16. ### Thermodynamics: Steam Plant

W3-4=852.44 kJ/kg Wnet=859.44 kj/kg Wnet=2.5783e04 kj/s qboiler=2.901e03 eff. = Wnet/qboiler * 100 = 29.63%
17. ### Thermodynamics: Steam Plant

Okay, my bad ^^", but the approach is correct, right?
18. ### Thermodynamics: Steam Plant

I can't what's wrong with W3-4. You know the first law of thermodynamics (for open systems) states: Q-W=m(Δh+ΔKE+ΔPE) [kj/s] Dividing both sides by m` q-w=(Δh+ΔKE+ΔPE) [kj/kg] Since q=ΔKE=ΔPE=0 -w=Δh --> w=-Δh --> w=h1-h2 Isn't that right?
19. ### Thermodynamics: Steam Plant

I'm not sure whether I'm applying the first law for closed cycle right or not (∑Qnet = ∑ Wnet). Should I take the signs in the account or not?
20. ### Multiple thermodynamics problems

My problem that I'm not sure of what I'm doing, so I took multiple and different problems and tried to solve them to test myself, and to be sure I put them here. Sorry for not following the template precisely, I don't have access to the internet all the time. Anyway, I will put the problems...
21. ### Thermodynamics: Steam Plant

Homework Statement The steam enter the turbine (3) of the steam plant at 8 MPa and 500°C. The steam extends in an isentropic process and leaves the turbine (4) at 200 kPa, then enters and leaves the condenser at constant pressure (You may treat the steam as a saturated liquid when it leaves the...
22. ### Multiple thermodynamics problems

Homework Statement http://imgur.com/a/6Ogpx Homework Equations H=U+PV Q-W=m(u2-u1) The Attempt at a Solution http://imgur.com/a/6Ogpx
23. ### Oscilloscope error

Homework Statement "An instrument (oscilloscope) is prepared to measure a sinusoidal periodic wave, compute the measurement error if the same instrument is used to measure the wave indicated in figure 1 (The wave is much more like a sawtooth wave, sorry for bad drawing) Homework Equations...
24. ### Designing an Ohmmeter

Homework Statement If you an Ammeter with Rm=50 ohms and Ifsd=0.5 mA, What is the voltage differece you should have if you want to design an Ohmmeter to measure the resistances below 110 kilo ohms? Also, determine the values of the minimum and maximum values of the voltage source that can be...
25. ### Multiple RLC problems

OK. And for problem b)?
26. ### Multiple RLC problems

I meant the equation for the voltage source itself. Also, I mean the equation for the source itself. For the average value, should I dismiss 2*Imax/pi?
27. ### Multiple RLC problems

Homework Statement a)[/B] For the following circuit, if Vrms= 40V, write the current and the voltage equations. http://www.imageupload.co.uk/images/2015/02/26/Captureaa814.png [Broken] b) For the following circuit, if i=0.8 sin(1000t-30), write the voltage equation and determine the average...
28. ### Three phase ac network

I found out that a purley inductor doesn't disspate any power, which leads to P=0. Thanks :)
29. ### Three phase ac network

Hi everyone, 1. Homework Statement Three inductors with 0.1 H each are delta connected to three phase ac newtork with 220V/50Hz. Determine Iph, IL, P, Q and Theta. Homework Equations Showed at the attempt. The Attempt at a Solution [/B] XL=2*pi*f*L=31.4 ohms Iph=Uph/XL=220/31.4=7 A...
30. ### JK Master-Slave Flip-Flop timing diagram

Here you are: http://www.circuitstoday.com/wp-content/uploads/2010/04/Master-Slave-Flip-Flop.gif And yes, I was given these waveforms.
31. ### An old Electronic textbook?

Nope. :( That's exactly what I need.
32. ### Flip Flops with direct inputs

Please, I'm not that lazy. I've the AND-NOR combination (which my instructor gave me and I'm not sure if it's right or wrong): I need to know the NAND combination because my instructor didn't gave me any method to convert between AND-NOR and NAND combinations.
33. ### Flip Flops with direct inputs

Hi everyone, What is the logic circuit of JK flip flop with direct inputs (Clear and Preset)? I need circuit with AND-NOR and NAND combinations if that possible. Thanks in advance
34. ### An old Electronic textbook?

Hi everyone, I need the book of which these problems is derived from. http://postimg.org/gallery/18f6og0ji/275e0c9d/ Any help?
35. ### JK Master-Slave Flip-Flop timing diagram

Homework Statement Draw the output Q of the JK Master-Slave Flip-Flop Homework Equations Master works at the rising edge, while and the Slave works at the falling edge. The Attempt at a Solution http://s13.postimg.org/j5ldpmw9i/20150109_095656.jpg
36. ### The area of a square with right triangle inside it

I got it now. Thank you everyone for your help. I really appreciate it.
37. ### The area of a square with right triangle inside it

Just fixed it. Sorry about that.
38. ### The area of a square with right triangle inside it

Homework Statement I need to find the area of the square in the following figure: Homework Equations Basic Trig relations. The Attempt at a Solution I aimed to find the length of BC, but first I had to find the unknowns of the right triangle CDE, which are EC=5m, <DCE=36.86ْ ...
39. ### Differential equations: Elimination of arbitrary constants

I'm using a method in which I differentiate depending on the number of constants. So, in this case I shall differentiate three times. y=e^{ax^{2}+bx+c} y'=e^{ax^{2}+bx+c} (2ax+b) y''=e^{ax^{2}+bx+c} (2ax^{2}+4axb+b^{2}+2a) y'''=e^{ax^{2}+bx+c}...
40. ### Differential equations: Elimination of arbitrary constants

Homework Statement Find the differential equation of ln y = ax^2 + bx + c by eliminating the arbitrary constants a, b and c. Homework Equations Wrosnkian determinant. The Attempt at a Solution I've solved a similar problem (y=ax^2+bx+c --> y'''=0), but couldn't do the same with...
41. ### Engineering Analyzing circuit with Silicon and Zener diode

Homework Statement Determine Vout, the current flowing through R and power power dissipated the Zener diode. Homework Equations Circuit analyzing techniques. The Attempt at a Solution I've done this problem by assuming each diode is off while ignoring the other. E.g...
42. ### Determining two diodes' currents

My circuit analyzing again :S Thanks :)
43. ### Engineering How to correctly redraw a circuit?

Ok, I just to make sure of something. When V1=V2=5V, the two diodes are reverse biased, then Vo would be 5V, isn't?
44. ### Determining BJT's voltages

NascentOxygen Thanks :)
45. ### Determining BJT's voltages

Actually, that what I'm asking for, the definition of the operating point. As far as I know, the operating point should be one of four regions: 1- Active (forward biased diode and reversed biased one) 2- Cut off (two reversed biased diodes) - 3- Saturation (two forward biased diodes) 4- Inverted...
46. ### Determining BJT's voltages

Drakkith: Yes, it's applied on the circuit. phyzguy: That makes sense. Now I want to determine Vcb, which is Vc - Vb. Now I've Vc, is Vb the same as Vbe (0.7)? And what's the operating point of the transistor?
47. ### Determining BJT's voltages

Hi everyone, I'm new to transistors analyzing, and I need a way to correctly identify the voltages. Let's take this circuit for example: Assuming that the Emitter is the common element (The one with arrow which is connected to the ground), then VBE would be: My questions...
48. ### Determining two diodes' currents

Homework Statement Assuming that D1 and D2 are ideals, determine ID1 and ID2 according to the table below. Homework Equations Circuit Analyzing methods (KVL, etc...) The Attempt at a Solution I've confirmed my solutions for the first three cases with final answers of the book...
49. ### Prove the following series

Homework Statement Prove that, by putting x=0 x=∏ in x^{2}=\frac{\pi^{2}}{3}+4 \sum\limits_{n=1}^\infty \frac{1}{n^{2}} cos(nx) cos(n \pi), that \frac{\pi^{2}}{8}= \sum\limits_{n=1}^\infty \frac{1}{(2n+1)^{2}} The Attempt at a Solution This a solved problem, I've understood the first two...
50. ### Engineering How to correctly redraw a circuit?

Okaaay. I understand now, looks like I have to basics at all. :S I want to evaluate Vo in case V1=V2=0. Forward bias means there's a current flowing and reverse bias means there isn't any current.