Questions tagged [energy]
Energy is defined as the amount of work that can be performed by a force, measured in joules (J). Energy is power integrated over time; power (W) is energy per second (J/s). This is a poor tag to use. Please consider if your question relates to energy as defined in physics; don't use it as a synonym for power or capacity.
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RF power transmission control in U-blox GSM modules
I am using the SARA-U270 GSM module and want to test energy-saving techniques. One technique I would like to try is power transmission control, adjusting the transmission power in dBm based on the ...
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Energy stored in a saturating inductor
We all know that the energy stored in an ideal inductor is \$E=\frac{1}{2}LI^2\$. However, real inductors with a ferromagnetic core don't have constant inductance. Particularly, when a specific field ...
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Connecting an energy meter with 6 CTs? [closed]
I want to install an energy meter to monitor the energy consumption of a transformer. The secondary side of this transformer is a parallel circuit, making it impossible to connect three current ...
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Lithium polymer battery size versus energy density
I am building a small device that needs to use a rechargeable lithium polymer battery. The dimensions I am looking for are 351125 { 35 mm (H) x 11 mm (W) x 25 mm (L) }, which is the standard way these ...
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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 ...
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Time average stored electric energy in a volume
I am studying the book Microwave Engineering Third Edition by David M. Pozar. At the moment I am at chapter 1.6. At the beginning of this chapter Pozar states that
In the sinusoidal steady-state case,...
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Average energy efficiency is very high
I am computing the energy efficiency of a wireless system, given by the ratio of how many bits are received over how many energy is consumed.
$$EE=\dfrac{bits}{joules}$$
For a given scenario, I have ...
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What makes it hard to lower energy and power consumption for a computation: looking for serious but pedagogical reference
I would like to get "general" culture about what limits engineers in reducing the power and energy consumption to compute.
Please correct me if I am wrong but for power, I know that there ...
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Whats the meaning of Im, Is and Ih
I would like to know what's the meaning for the abbreviations of Im, Is and Ih in leakage currents measurements, as it is depicted in these graphis. Could anyone help me?.
The link of the source is: ...
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Why does the valve symbol have a Clase symbol,or short-circyit symbol before the earth [duplicate]
Could anyone explain to me why the valve symbol have a shortcircuit symbol or termination symbol before the earth???
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Meaning of this power system line diagram symbol
Please explain to me what this symbol means, in single line diagram?
Source of image: My project diagram.
Here is another example I found:
Here is a magnified part, showing the symbol:
Source of ...
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How can I store a energy from a low output?
I need a simple answer to a simple question: How can I store energy as in a battery to use it as energy for an LED lamp or something else? The available power is 50mV- 60mV and 70mA - 80mA.
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Potential energy of a uniformly charged parallel plate capacitor filled with dielectric
For a uniformly charged parallel plate capacitor (dimensions l × w × d), its potential energy is given by:
$$ U = \frac{Q^2}{2C}\ $$
Now if we insert a material (dimension x × w × d) of dielectric ...
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Energy density vs voltage battery
I find on this website the following sentence:
It is said that higher voltage battery have higher energy density. But it appears to me not so evident:
If I consider the 2 following batteries:
If I ...
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CMOS (Energy Supply of voltage) [closed]
Can someone please explain why, when \$ln\$ is transitioning from low to high, the energy supplied is \$C_{vdd}\cdot V_{dd}^2\$?
