All Questions
Tagged with energy efficiency
16
questions
1
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1
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Most energy efficient way to make a LED blink using a multivibrator [duplicate]
I'm using this LED. I want to make this LED blink at MAX brightness (100 mA) at 1 Hz. I need to use a multivibrator and therefore can't use any IC chips. The circuit is powered by a 3.7V battery with ...
- 11
0
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0
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428
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Energy-delay-product vs. Joule to watt conversion formula
I am currently on my master's doing an assignment, and I am in this point in time extremely confused and I was wondering about this, quite possibly, stupid question. I am just too afraid to ask at ...
0
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0
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33
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Microwave oven approximate efficiency [duplicate]
I just made popcorn in the microwave and I wonder how much energy my popcorn absorbed and how much energy was consumed by oven. It was 90g of corn and butter (kind of...) and it needed 800W for 3 ...
- 6,024
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127
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Mismatched rating in Ah and Wh. Why is that?
My question concerns the apparent mismatch between the Wh rating and the Ah rating often found on batteries.
On one of my batteries the label says:
12V Leisure Battery TR350 TUDOR EXIDE DUAL 80Ah, ...
- 11
3
votes
3
answers
1k
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Where does all the electric energy get dissipated in any electrical system?
I know that some portion of the electrical energy is dissipated as heat due to the efficiency, but where does the other energy go?
If we are talking about a satellite in space, all of the electrical ...
- 139
4
votes
2
answers
238
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Energy efficiency in an electrical circuit
I’m in high school and we are going to do this laboratory in which we will have to make two solutions at different concentrations and determine which has the greatest electrical resistance in a ...
- 41
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2
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112
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Lighting System in terms of its efficiency and consumption
I'm curious regarding some matters in my experiment session of Efficient Lighting System. There are 4 types of lamps which we measure the data to fill-in the table as in the picture. Correct me if my ...
- 11
1
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0
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106
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Battery Ah specs vs actual Wh when charging and discharging
It is ubiquotously stated that Wh = Ah x V. While this is true (at least regarding the units) I have some doubts about the practical aspects of it.
Using an example:
Let's take a fully discharged (0%...
0
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1
answer
58
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Does the size of switch-mode adapters affect their efficiency?
I know that a rule of thumb to judge the efficiency of a traditional iron core transformer is to look at its size: the larger it is, the higher the number of windings, the larger the core, the ticker ...
- 3
0
votes
2
answers
351
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Energy lost in in Peltier device?
Suppose I power a Peltier device to heat up/cool down some water. Then I later use the same Peltier device, in reverse, to convert the separated heat energy back into electricity.
I have read ...
- 101
-3
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1
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309
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Energy usage: CPU vs Screen vs Network [closed]
In a modern computer such as a smartphone, what is the relative energy used by the CPU vs the screen (and controller) and network? Clearly the answer to this question is (in so many ways) "it depends" ...
- 295
0
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1
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60
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Efficiency of Parabolic Trough
I just started learning this in class and am not understanding how to answer.. A parabolic trough has an active area of 18.1 m2, and produces 2960 W of power. The average solar power that falls on the ...
0
votes
2
answers
161
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Transformer drawing 29x more current than it needs
I have an old transformer (20+ yrs) in a building I manage (GE Model 9T23B3872), it takes 277V 3-phase and converts it to 120V 3-phase. It seems very wasteful. It is drawing a combined 8.7 A @ 277 V ...
1
vote
1
answer
2k
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Measuring Li-Ion Battery voltage during charging/discharging
I am supposed to measure a Li-Ion Battery cell's energy efficiency. For this purpose i have built up the apparatus setup which charges and discharges the battery cell to calculate its energy.
One ...
- 553
1
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1
answer
3k
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Energy efficiency of Li-Ion Battery
My question is that does the energy efficiency for Li-Ion battery varies for different C rates ? For e.g if a battery is charged and discharged at a lower C rate, would it's energy efficiency would be ...
- 553