Questions tagged [math]

Math or Mathematics is the abstract study of topics such as quantity (numbers), structure, space, and change.

Filter by
Sorted by
Tagged with
0
votes
2answers
83 views

please explain this fourier equaton

reference from here why are there 2 exponential terms on right side of equation in red box ? i know euler identity but why does ,the left side is trigonometry form when n=1 equal to exponential ...
2
votes
1answer
40 views

Trying to find value of two capacitors using resonant frequencies in three conditions, but wrong formula is derived

I was trying to find capacitance of two capacitors in the following way. Connect each capacitor individually to a same inductor and find resonant frequency in each case. Connect the same capacitors ...
0
votes
0answers
42 views

Diode sine wave shaper - location of break points

I'm attempting to generate a sine wave from a triangular wave using the diode breakpoint method where the sine wave is approximated by multiple straight-line segments. Where should the breakpoints be ...
5
votes
3answers
1k views

Implementing an absolute value function in C

I am implementing a function to find the absolute value like this: uint16_t absolute_value(int16_t n) { int16_t mask = n >> 15; return ((n+mask)^mask); } ...
1
vote
2answers
102 views

How to find the right smoothing capacitor for rectification circuit

I am creating a power supply which will need to convert the 24vac to 5vdc. I am thinking of using a rectifier to convert ac to dc, then a capacitor to smooth out the voltage, then an LM2596-5 to drop ...
0
votes
0answers
17 views

How to convert T matrix to Z matrix in two port network?

How can I transform a T matrix to become a Z matrix for a two-port network? I found the following conversion to get the T matrix from Z matrix from here : https://www.tutorialspoint.com/...
0
votes
0answers
61 views

Find the transfer function of an opamp circuit

I've the following circuit: simulate this circuit – Schematic created using CircuitLab I need to find the transfer function of this circuit. I did the following: $$V_+=\frac{R_1}{R_1+R_2}\...
0
votes
0answers
30 views

Cooling Peltier Maths

I want to construct a peltier cooling system. However, I have limited mathematical skills. Can I ask how to do the maths to calculate how much temperature differential can a specific peltier cool ...
2
votes
3answers
57 views

Class A amplifier - Transistor Q-Point calculation

Reference: http://www.learningaboutelectronics.com/Articles/How-to-find-the-q-point-of-a-transistor-circuit I am trying to understand this q-point calculation. I recently asked a question about the ...
0
votes
1answer
59 views

DC Analysis of Transistor Circuits - Double vertical line symbol

I have stumbled twice across this symbol || being used in the analysis of transistor circuits. An example can be seen at this address: http://www....
2
votes
1answer
72 views

Second order RLC circuit problem about signs

Consider this circuit. Which is a second order RLC circuit. The problem asks for value of \$\phi\$ from the initial conditions. I took the first derivative of the equation by hand but as you'd see ...
0
votes
1answer
70 views

Impedance load matching

So I've done this so far, and know one of the components is a 50ohm resistor. However I dont know where to go from here. How do i decide if its an inductor or a capacitor? This is a past paper exam ...
0
votes
2answers
94 views

Current in charged RC circuit

I've the following circuit: simulate this circuit – Schematic created using CircuitLab The capacitor is charged up to 10 V according to the following formula (when the switch is closed): $$\...
0
votes
1answer
75 views

Maximum safe working voltage of capacitors

The answer is 30kV. My method led to an answer of 41KV, where did I go wrong? I believe I cant just add the Vmax(s) at the end, but what would I do instead and why?
0
votes
0answers
56 views

Help with determining the open circuit voltage

Can someone go through why Vxy= -84mV? Given the values off VB=180mv R1=22ohms R2=68ohms R3=150 ohms. Many thanks
2
votes
3answers
84 views

Mathematical help with Wheatstone bridge

This is a homework, so I won't ask for a complete solution, but can anyone tell me how should I approach this? I've been sitting now for hours without any progress, all that I know is the answer ...
2
votes
2answers
68 views

Where did this useful matrix decomposition come from for Nodal Analysis?

Background The equations formed when finding the nodal voltages of a circuit can be expressed using nodal analysis as a square system matrix \$\mathbf{S}\$ (lets say \$m\times m\$ where \$m\$ is the ...
0
votes
1answer
66 views

boolean algebra question regarding how to simplify a 5 input circuit

Background: I'm teaching myself computer architecture because I do not have a technical degree and want to learn this even though my finances won't ever allow me to have a formal education. I am doing ...
1
vote
2answers
64 views

I need an equation to calculate the time for a power percentage of a half cycle sine wave into a resistive load

I need to calculate the time a thyristor/triac needs to be on for a desired percentage of full power of each half cycle of the AC line input. On for the full half cycle will give me 100%. On for 1/2 ...
0
votes
0answers
46 views

Differential amplifier solving equations for iDS

In large signal analysis of differential amplifier there are some equations to determine iDS. If we simplify it looks like that : \$ \large 2x^2+2kx+k^2-2\frac{l}{m}=o\$ Is there an easy way to ...
2
votes
0answers
23 views

Price as a function of load on an electric grid(City modeling)

Thanks for your time. First some context and the actual question is marked further down. Context: I am modeling a city as a complex adaptive system and am building a model of an electric grid to run ...
0
votes
1answer
71 views

There is no math for adding the functions of two parallel filters. Or is it?

I want to add two "parallel" functions. Each of them describes the frequency response of that individual filter. Put in other words, I want to see what the frequency response looks like when the two ...
0
votes
1answer
68 views

Clarity on dB SPL calculation

Based on this post, let me assume that I have a input source of 94 dB SPL / 1 Pa that a microphone is picking sounds from. The microphone has a sensitivity of -46dBV/Pa , this gives 0.005012 V RMS/ ...
0
votes
1answer
37 views

Discrepancy in my dB SPL calculations

Having read through this post I tried an experiment. I connected a Extech sound level calibrator to a Type 4189 microphone. The output sensitivity of the microphone is 50 mV/Pa,-26 dB ± 1.5 dB re ...
0
votes
2answers
59 views

Deriving Capacitor Current Equation

I understand that the current through a capacitor is given by the capacitance multiplied by the rate of change of voltage. I also understand that this leads to infinite impedance for DC and virtually ...
0
votes
2answers
85 views

Fourier series coefficient for sin(wt+theta)

Am trying to find the Fourier series coefficient ck for the following function \begin{equation} x\left(t\right)=\sin\left(wt+\theta \right) \end{equation} Here is my work \begin{equation} c_k=\frac{1}{...
1
vote
2answers
140 views

Finding the average power dissipated in a resistor

Well, I've a series RL circuit that is powered by a voltage source. The input voltage is given by: $$\text{V}_{\text{in}}\left(t\right)=50+\frac{400}{\pi}\cdot\sum_{\text{n}=1}^\infty\frac{\sin\left(...
-1
votes
1answer
46 views

Transforming a supply power [closed]

For a recent project i need to power a certain element with .7 amps and 5 volts. my input power is 5 volts, but i need to calculate a circuit for decreasing current. I looked for answers on google and ...
0
votes
4answers
104 views

Sinusoids represented using Euler's formula notation, confusion

EM plane waves are represented using the equation (ignoring amplitude) $$E(x,t) = e^{j (wt - kx)}$$ They are also represented in this form: $$E(x,t) = \cos(wt - kx)$$ I want to get the electric ...
0
votes
0answers
54 views

How to calculate the current produced by a solar panel?

The equation for calculating current when given voltage and temperature is known as the 5-Parameter model ie. \$I = I_{ph} - I_o[\exp(\frac{V + R_sI}{nV_t})-1] - (\frac{V+R_sI}{R_{sh}})\$ Since this ...
0
votes
2answers
61 views

Graphical nature of signal energy

In signals, we learn that the energy of a signal is the integral of its square. E.g. \$E=\int_{-\infty}^\infty x^2(t) dt\$ We know that integrals are the areas under the function in a graph. But ...
1
vote
1answer
43 views

Explanation of 5 Parameter Model for Solar Cells

I am having a hard time understanding this equation, the 5 Parameter model for photovoltaic cells. \$I = I_{ph} - I_o[\exp(\frac{V + R_sI}{nV_t})-1] - (\frac{V+R_sI}{R_{sh}})\$ My goal is to apply a ...
-6
votes
1answer
64 views

How to calculate the transmission distance from satellite to earth (How to understand the formula) [closed]

I have this question in one of my tutorials and I cannot seem to find clarity in the question - I am trying to make an algorithm to do this all automatically but I need to understand the formula I ...
0
votes
0answers
48 views

RLC circuit with intial conditions

The circuit I have is given by the following schematic: simulate this circuit – Schematic created using CircuitLab I know a few things: The current in the circuit at \$t=0\$ equals \$\text{I}...
0
votes
2answers
132 views

Connecting the following structure of multipliers and adders in an elegant way in verilog

I am attempting to write a synthesizable verilog (or Systemverilog) module. I also want to make the modul parameterizable, which has presented a problem when trying to connect the following structure ...
1
vote
1answer
112 views

Compensate centrifugal force in accelerometer measurements

I'm working on a project that includes counting the revolutions of a cylinder connected to an engine. This engine runs at a minimum of 5 revolution per second and a maximum of 9 revolution per second. ...
1
vote
0answers
45 views

How do you calculate average absolute value of a sum of sin functions with different amplitudes and frequencies?

I cant seem to find the answer anywhere. I remember there was a simple formula for doing this but I dont have the book with it anymore. Finding where the function is positive and where is negative and ...
0
votes
2answers
146 views

Conversion from dBm to dB\$\mu\$V?

I am trying to derive the conversion from dBm to dB\$\mu\$V. So, please correct me If I am wrong. \begin{align} \textrm{dBm} &= 10 \log_{10} \left( \frac{P}{1\textrm{mW}} \right) = 10 \log(P) + ...
0
votes
1answer
123 views

Convert ADC value to real voltage

I want to measure the input voltage to my circuit. The input voltage is supposed to be anything between 7 to 35 Volts. I have a micro-controller with 12bit ADC. I am using a simple voltage divider to ...
-1
votes
2answers
3k views

Calculate battery state of charge percentage

What is the correct formula to calculate battery state of charge percentage based on the battery type (12v, 24v, 48v and so on) and the current battery voltage. For example if I have a 12v battery ...
4
votes
3answers
169 views

Order of precedence for parallel operator

In electrical engineering the parallel operator || gives half the harmonic mean of two values. E.g.: \$R_1 \parallel R_2 \equiv \frac{1}{1/R_1+1/R_2} \$ But how should you compute \$kR_1 \...
0
votes
1answer
111 views

Control Theory Integrator Phase Shift

Guess I should know the answer, but I can't come up with a good explanation. I always have to remember which sign cos and sin have after integration/differentiation. I usually do this by thinking of ...
0
votes
1answer
52 views

Finding current over controllable voltage source using nodal analysis

I have the following circuit: Let me explain the diagram a bit first: I0 is current in that direction, V0 is voltage and 2 V0 is also voltage times two. V1, V2, and V3 are my nodes. The 'S' by the ...
29
votes
5answers
14k views

Why is the time constant 63.2% and not 50% or 70%?

I am studying about RC and RL circuits. Why is the time constant equal to 63.2% of the output voltage? Why is it defined as 63% and not any other value? Does a circuit start working at 63% of output ...
1
vote
1answer
83 views

Finding the fourier series coefficients of the signal $$1+\sin (\omega_0 t) + \cos (\omega_0 t) + \cos (2\omega_0 t + \pi / 4) $$

I have come across this question that asks to find Fourier series coefficients of the following signal. $$1+\sin (\omega_0 t) + \cos (\omega_0 t) + \cos (2\omega_0 t + \pi / 4) $$ In my intuition, ...
0
votes
1answer
62 views

Control Theorie: Drawing Transition Matrix Trajectories

Given a transition matrix like e.g. $$ \phi(t)=\begin{bmatrix} e^{-3t} & 0 \\ 0 & e^{-3t} \end{bmatrix} $$ What is the analytical way of drawing x(t) for two given starting points? I only ...
0
votes
1answer
53 views

Multi phase vs single phase power factors

Are there any differences between calculating single phase and multi phase power factors? I'm open to general answers, but more specifically: If PF1=P/S, does PF3=(Pa+Pb+Pc)/(Sa+Sb+Sc)? Does ...
0
votes
1answer
40 views

2D Positioning Localization

I have a robot. My robot has three main sensors one is a gyro from which i can get my yaw, pitch, and roll. I also have an encoder in the x and y axis. How can I use these sensors together to reliably ...
2
votes
2answers
86 views

In a Wilson mirror, does Q3 need to have the same beta to cancel the base current error?

I'm learning about Wilson mirrors in the Art of Electronics Third Edition (pg. 102). It shows the following circuit: simulate this circuit – Schematic created using CircuitLab It then ...
1
vote
0answers
99 views

Calculation of Euler angles. But gets a change (delta) in change and not a constant value

What I've done will now: I'm using an IMU (MPU6000) to calculate the Euler angles of an object and for this, I'm using Madgwick AHRS algorithm. The MPU gives acceleration due to gravity (a) about the ...