Questions tagged [homework]
Use this tag if the question you are asking is an assignment or homework with which you require assistance. EE.SE is not a homework answering service, so make sure you show what you have attempted so far and are specific as to where you have gotten stuck.
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How to find the power factor of a component when the combined power factor and one other power factor is known? [closed]
Problem:
A 2000 volt-ampere with a power factor of 0.8 lagging is combined with 500 volt-amperes of
synchronous motors. If the overall power factor is 0.9 lagging, find the power factor of the
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How to calculate transformer iron core losses?
For a 3 phase, 60 Hz, 6600/690 V, star/delta transformer
Rating is 2500 kVA
At full load unity power factor it has an efficiency of 97%.
Maximum efficiency occurs at 2/3 of the full load
How to ...
2
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1
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Electromagnetics - Calculating electric field vector given an equipotential surface
I'm trying to figure out how to calculate the electric field vector given an equipotential surface with the equation \$ x^3 + y^2 +z = 1000 \$ where x, y, z are positive. The potential on the surface ...
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differential gain for mismatched \$g_m\$ in differential amplifiers
I couldn't understand how the author came up with the expression of differential mode gain. He states to look from the Fig 4.17 to derive this expression, whereas the fig 4.17 has no mention of \$R_{...
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How can i obtain a positive Vref for this circuit?
I have to design a irrigation system that uses a resistive moisture sensor to maintain a certain level of relative soil humidity for a plant. In order to convert the resistance changes of the moisture ...
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Analyzing \$g_m\$ vs \$V_{in}\$ for a common source config
I had this doubt while going through the book "Design of Analog CMOS Integrated Circuits" by B. Razavi, if we are to plot \$g_m\$ vs \$V_{in}\$ for the above circuit, then we have \$g_m\$ =0 ...
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What is the name and purpose of this part?
We disassembled an automatic electronic blood pressure monitor to find out its parts. While looking into the names and uses of various parts, I found that this part alone did not have a part number ...
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JK flip flop timing diagram
Is this JK flip flop timing diagram for the Q output correct? I just want to make sure I didn't mess anything up.
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Solving for current flowing through R and reflection coefficient
This is my attempt at solving it. I'm not sure if it's correct, so I thought of asking for some advice.
Image of circuit:
Values:
ABCD matrix:
So I'm supposed to solve for the reflection ...
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Calculate the absolute value difference in work function for two diodes
Given two semiconductor diodes where one is silicon and the other is called Graham, and both are connected by ideal wires that do not affect their work functions, and they are also in thermal ...
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How can I calculate the base current required for my multistage connected PNP transistor to obtain an obtain an output collector current Ic = 1.5A?
I need to design a circuit that provides an output of 11.5V with a current of 1.5A. This output is drawn from a TIP42 PNP transistor. The transistor gets its base input from a NPN2222 transistor.
The ...
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Is it possible to achieve a square root analog filter?
I am attempting to create a (3/2)th-order active low-pass filter circuit, with a zero[es] at ω=10000 and pole[s] at ω=100. The only way I can think to do this is to simply cascade three simple first-...
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How to go with this RC circuit?
So, i've been asked to get the differential equations (or model) for this circuit:
V1=15 u(t)V, R1=10 ohm, R2 = 20 ohm, C1=10uF, C2=20uF
I'm just a beginner, and don't know if the differential ...
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Solve problem about voltage drop [closed]
Can you please help find the voltage drops at 8 Ω and 20 Ω?
Reference below.
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Charging a mobile phone and laptop using wall plug - Series or parallel circuit?
I'd like to understand if charging multiple devices using the 240 V line's main power plugs forms a series or parallel circuit.
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