Recent content by Goliatbagge

I am a supervisor for a student's high school project. He has acquired a small superconductor of Bi-2223, specifically this one: https://shop.can-superconductors.com/hts-demo-parts/11-superconducting-bi-2223-bar The superconductor is just a couple of centimeters long and a few millimeters wide...

Love this animation! Thank you!

Ok, so let me get this straight. The resultant force in a circular motion is always pointing to the center if, and only if, the motion is at a constant speed. For example, if we are spinning a weight attached in a string vertically in a gravity field it will NOT have constant speed and therefore...

Suppose we have a vertical circular motion with gravity according to the image below. In the leftmost and rightmost positions the resultant force is pointing diagonally down. Isn't the resultant force supposed to be pointing at the center at all times in a circular motion? What am I getting...

:biggrin: Since temperature is a measure of mean kinetic energy of atoms, then the temperature should be zero when all atoms are in rest. So, in a strict physical sense, I think the Kelvin scale is the most logical one. With that said, I would not use the Kelvin scale in every day life...

Thank you king vitamin and Bandersnatch for good answers and for understanding my question! Even though the word "degree" is used in many areas, it's still quite interesting that the degree sign is used both regarding temperatures and angles. Personally, I'm glad that they dropped the degree...

I know it's not the same thing. I just wonder why (historical) they decided to measure temperatures in degrees? They could have chosen to measure temperatures in just C or F instead of °C and °F? Temperatures doesn't have anything to do with angels.

Why is it that temperature is measured in degrees (degree Celsius, degree Kelvin etc)? Does it have anything to do with "angular" degrees?

Does it exist a numerical method to calculate for example sin (42°), sin (43°), sin (44°) etc by hand?

So if two photons appear from vacuum their sum of energy should be zero? Wouldn't that mean that one of them must have negative energy?

Photon and "anti-photon" annihilation? In quantum field theory pairs of virtual particles can appear from vacuum and quickly annihilate each other, for example an electron/positron or a proton/antiproton. But how does this work with photons?From what I know, the photon is its own anti-particle...

I get fooled by the time dilation. It's just hard to imagine that an event (e.g. an explosion) in one perspective can take place "before" it happened in another perspective. It "feels" like you can prevent something that already took place in another perspective. I know this reasoning is wrong...

Thanks for your answers! I totally forgot Lorentz' length contraction. I get what you mean. So here is a follow-up question. At point B, we have a bomb that detonates when struck by a photon. From the spaceship observer's perspective the bomb will detonate before the photon from Planet A:s...

Imagine this race. A beam of light is emitted from a planet (point A). Of course this beam will travel in the speed of light relative to the planet until it reaches point B. Starting at the same time as the beam, a spaceship travel from point A to point B (its speed is arbitrary). The speed...