All Questions
Tagged with electricity electrical-engineering
69
questions
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54
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How much energy do I need to charge an electric car? [closed]
Suppose I have an electric car with a battery capacity of N kWh, how many kWh of power do I need to recharge it? It can't be a precise match of N - some must be lost through heat, powering the ...
- 101
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74
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Modelling behaviour of a transformer
I'm looking for a physical-mathematical model to describe the behaviour or working point of a power transformer in dependency on its most critical parameters like oil temperature/heat dissipation, ...
- 1,507
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2
answers
2k
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Can an Oven being set to a different temperature cause electric board to go off?
Basically: the electrical system kept going off (when light goes down in a division due to too many electrical appliances on at a time, or their combined power consumption).
My roommate said it was ...
- 101
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votes
1
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368
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Can incandescent light bulb can be brighter if fixed power?
I found that luminous efficacy of 60 W tungsten incandescent bulb is 14.5 lm/W.
Is this value defined by design details listed above or it depends on something else too?
Can we design 60 W tungsten ...
- 1,732
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285
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How do cathode ray tubes (CRT) synthesize colours?
I just read about how LCD displays were based only on black&white contrasts, and only colour filters on each subpixel generated the colour of a pixel. However, how does that happen for a CRT?
Is ...
- 995
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59
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Applying more current? [closed]
An electric motor draws 20 Amps, when at maximum load of x.
Can that value of current be applied even if the load was ten times less than x from a certain power source?
- 1,110
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75
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Ramsauer–Townsend effect and Thermal Runaway in Thyratrons / (vacuum tubes)
A few years ago an EE told me that the Townsend effect was involved in thermal runaway within vacuum tubes. I can't seem to find any specifics on this on the internet. Can anyone disprove / verify and ...
- 23
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25
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Do you get correct graph of transfer characteristic, if you take +ive Vds(constant) value instead of -ive. As mostly CNTFETs are p-chnl FET
I'm studying transfer characteristic curve of CNTFET to get value for mobility, S.S, etc. According to my basic background knowledge, NMOS curves lie in the 1st quadrant. While for PMOS they lie in ...
- 11
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1
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315
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What causes changes in frequency in the Nation Grid electricity supply? [duplicate]
Following the power cuts in Britain this week, we were told that lack of power being generated led to a drop in the AC frequency as shown in this graph:
I understand why a stable frequency is ...
- 101
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2
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54
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Current law explained
Kirchhoff's Current Law (KCL) is experimentally proven but what exactly happens?. I have made a model by taking the drude model and adding the interactions between the electrons and the reason why ...
- 49
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2
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1k
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How to calculate total power generated?
I have a circuit with a piezoelectric transducer which converts mechanical energy to electrical. The ceramic is connected to a 1 Megaohm resistor and a voltmeter which reads voltage.
If I want to ...
- 15
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294
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What is the uncertainty on 50 Hz a.c.?
We are doing an experiment to measure velocity using the ticker-tape timer which runs on a 50 Hz a.c. 12 V power supply. I am in Ireland. So the time interval between each pair of dots is 0.02 s. But ...
- 1,329
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1
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640
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Potential difference between two points
Okay so this might sound kinda stupid but I'm new to electrostatics and I was doing a question that asked me to find the potential difference between two points . Now I calculated the potential at the ...
- 53
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1
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26
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Piezoelctric Ceramic Transducing Capabilties
Piezoelectric ceramics are able to work as transducers, outputting electrical energy when mechanical stress is inputted. However, most ceramics have high static voltage and low current and power ...
- 15
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48
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Resonance curve of oscillating curcuit
I took a resonance curve (see below) for different (series) oscillating curcuits plotting I:f and found that the amplitude differs for different values of C and L. Why exactly is that?
Blue specs: $L=...
- 141