Physics: Why do we describe light by referring to its wavelength, but microwaves and radar pulses by referring to their frequency?

In physics, the description of the properties of light generally refers to its wavelength (nm), while in the range of microwaves and radio waves we refer to the frequency of a signal (e.g. kHz or...

03 March 2021 1,682 3 View

Irradiation data for JAPAN?

Hi, Could you help me to get the latest (2019, 2020) solar resource data for a particular site in JAPAN? PV GIS and NSRDB data are not in reach to JAPAN, I'm looking for some other database for...

03 March 2021 961 3 View

Why are the velocities so high in my Boussinesq approximation Fluent simulation?

Hello, I have a mechanism where air rises due to convective flows. In this simulation, nothing is driving the air except this. I understand that the Boussinesq approximation only works for small...

02 March 2021 4,910 3 View

Why almost every element would be metallized in sufficiently high pressure and low temperature?

(This statement is from wikipedia, BTW). What is so special about metallic bond that is limiting high-P low-T state of a matter (as long as individual atoms exist, not white dwarf of neutron star...

02 March 2021 3,309 2 View

How Relativistic effects is one reason for lanthanide contraction?

The Lanthanide contraction which is the decrease in ionic radii of the elements in the lanthanide series from atomic number 57, lanthanum, to 71, lutetium, is due to poor shielding of the 4f...

01 March 2021 2,272 4 View

What is the density for pva electrospining?

I'm Juan Carlos, a high school student who is working with electropinning, I made an electropinning machine with a 21g needle and a 30kv high voltage source and the distance between my needle is...

28 February 2021 298 3 View

Is there a deep reason for using the squared modulus of the wave function as the probability density of the existence of the particle?

I think we were all surprised at the first time we got to know quantum mechanics that the squared modulus of the wave function is the probability density of the existence of the particle? The role...

28 February 2021 6,282 9 View

How to Eliminate cosine error and abbe error in LASER measurement system(for example Rhenishaw XL80)?

I like to do project in laser measurement system. My objective is to eliminate or reduce the cosine error, abbe error in Laser measurement system. I have Rhenishaw XL80 system. Please tell the...

28 February 2021 4,890 3 View

Should we reduce the standard unit of length to 0.31951540592 meter ?

The reasoning behind this question is to align the ratios of the proton potential in energy per charge to the speed of light in distance per time. As these two dimensions appear to be related,...

27 February 2021 947 7 View

How to measure angle between laser travel path and machine axis in Laser Measurement system?

25 February 2021 1,987 3 View