Category: Physics

Hydrogen Production through Electrolysis

Hydrogen Production through Electrolysis

Hydrogen Production through Electrolysis

08/26/18

“How can we produce hydrogen using electricity?”

 

Hydrogen is an amazing material. However, extracting it can be quite difficult. One way to do it is to take an anode and a cathode separated by an electrolyte and a membrane. The water will react at the anode to produce oxygen and positively charged hydrogen ions. The electrons will flow through the circuit and the hydrogen ions will move across the membrane to the cathode side. They will then meet and recombine to form hydrogen molecules. This way, we can Produce Hydrogen using Electrolysis. Since the only thing that needs to be added to the system is electricity, if our grid is powered by renewables then we can have a carbon neutral method of hydrogen production!

 

Image credit Department of Energy

Sigma Heat

Sigma Heat

Sigma Heat

07/28/18

“How can we calculate the specific energy for humid air?”

 

Air can vary a lot in both temperature and humidity. And sometimes, we would like to know the specific energy for humid air under constant pressure at a reference temperature ignoring the effects of condensation. To do this, we can calculate by the Sigma Heat S = 17.86 (kj/kg) + 1.05 (kj/kg)*t + W(2501 (kj/kg) + 1.884(kj/kg)*t), where t is the dry-bulb temperature of the air (in °C), and W is the specific humidity of the air (no unit). The Sigma Heat equation is commonly used in mining engineering to calculate the temperature regulation of mine air.

Quasistatic Processes

Quasistatic Processes

Quasistatic Processes

07/14/18

“Can a thermodynamic process be so slow that it’s almost static?”

 

Thermodynamic processes can happen over any period of time. Sometimes they happen so slowly that they almost seem to be static. These Quasistatic Processes are often used in analysis of Iso-Processes due to their stable nature.

Band-Pass Filters

Band-Pass Filters

Band-Pass Filters

07/08/18

“How can we combine a low-pass and a high-pass filter?”

 

High-pass and low-pass filters are great for attenuating signals to certain extreme frequencies. However, sometimes we would like to only have a certain range of frequencies neither high nor low present instead. This is where we can use a band-pass filter, which limits the frequency range to a certain bandwidth.

Dither

Dither

Dither

07/07/18

“How can we fix signal noise by inducing noise?”

 

When converting a signal from a higher-bit to a lower-bit resolution, unpleasant noise can be induced. To fix this, we can add in some low-volume noise called Dither before the conversion, effectively eliminating the truncation error. Dithering is commonly used in audio sampling during file compression.

Demodulation

Demodulation

Demodulation

07/05/18

“How can we extract information from a signal?”

 

Modulation is amazing for transmitting signals along great distances. However, in order to retrieve their information we have to revert them back to their original form. This can be done with Demodulation, usually done by multiplying the received signal by a signal identical to the Carrier Signal to rectify it.

Modulation

Modulation

Modulation

07/05/18

“How can we transmit information through signals across long distances?”

 

Audio signals are great for transmitting information from one place to another. However, they lack the ability to travel far. So how can we get around this problem? Well, radio frequencies happen to be very capable of traveling great distances. So why don’t we merge our audio frequency Modulation Signal with a radio frequency Carrier Wave to get a new, information-rich, distance capable Modulated-Carrier Signal? This is the idea behind Modulation and is one of the most fundamental parts of radio transmissions.