Classical Physics

I think that there is a Swiss company that can etch any company logo or text into glass in such a manner that the glass appears clear to the human eye, until light projects the image on to a surface behind it. I just can't find that company, is this real or did I imagine it ?

A question in a very famous physics book in my region is as follows: While walking on ice, one should take small steps to avoid slipping. This is because smaller steps ensure: a) larger friction b) smaller friction c) larger normal force d) smaller normal force This is a single correct multiple choice question. Contrary to common idea, which is that smaller steps would give you more friction, the book states the opposite, smaller steps would give smaller friction!? So as per my reasoning, in both the cases, the normal force would be the same, equal to mg, where m is the mass of the person, to maintain vertical equilibrium, so option…

Hello all, I have just found Falstad and have a couple of questions to ask please. I connected an led to a 50 volt battery with a 100 ohm resistor. The led still lights. Shouldn't it burn out (diagramatically of course) or is it that the programme doesn't have this facility? Perhaps my sums are wrong, I am a beginner after all. How do I have a two way (double) switch on this programme? I would like to experiment with a capacitor and a lamp. Thanks in advance everyone.

I examined the articles and videos about 'the tin can phone'. I concluded that all the articles and youtube videos about it are fake. But now let's understand why the tin can phone articles are bullshit. Let's examine wikipedias article en.wikipedia.org/wiki/Tin_can_telephone Basically they begin their article saying it works, without providing any technical prove. The whole article is anti-scientific bullshit. They say: "When the string is pulled taut and someone speaks into one of the cans, its bottom acts as a diaphragm, converting the sound waves into longitudinal mechanical vibrations which vary the tension of the string. " . In this quote, the…

I enjoy taking my Jeep up into the mountains on rough trails. I have gotten into an argument with some of the others that also enjoy this pastime. I was hoping you guys could settle a dispute about locking differentials. Background I think this is mainly a science question. You don't have to know much about cars but you do need to know the following: Open Differential This is the most common differential found in almost all cars and trucks. Lets say a car with an open differential has the left tires on dry pavement. The right tires are in snow covered ice. If you have an open differential and you hit the gas your right tire would just spin in the ice and s…

What cause short circuit, why it can cause fire?

I know Perpetual motion is a losing battle, however, i was curious what would happen if someone mounted the most effective version of a large BHASKARA'S Wheel onto the center axle of a well constructed perpetual water mill design? Since they both "Almost" work on their own, would it make any difference if these two designs were combined into one machine?

Hi! I am new there. Right now i'm writing a paper on granular motion and dymanics of two-phase solid-gas systems (smoke, aerosoles, etc). Planned to use Chorin A.J. Vorticity And Turbulence for citations and calculus, but found out, this book does not cover up two-phase flow. If there any gas dynamics pros/scientists, what book or articles can you suggest to look for? I am not aiming for strong math backup, but it would be great addition to theory, if book has one. Looking forward for your suggestions!

Given 2 gravitational points in a close oscillatory relationship and a 3rd at a relativly greater distance, how would I demonstrate mathematically that the influence of the first 2 upon the 3rd decreases as the distance between the first 2 increases? Assume the oscillatory relationship to be circular, or an average.

which is worse, If a person touch an iron pole, and a TASER gun hits him/her, or If a person touch an iron pole, and a TASER gun hits the iron pole Will the person die in both cases?

In Millikan's oil drop experiment, when the oil droplets fell through the hole in the top plate, and passed through the ionised air, did only electrons get attached to the droplets? Or both the electrons and the cations? In my book, only electrons are shown as attached to the droplet. Why only electrons got stuck? Why not the positive ions as well? Or did they?

Suppose there are two meteorites which approach the atmosphere of the Earth from different ( maybe opposing) directions. Let us assume that the atmosphere is at rest with respect to an observer at ground level. At the moment that the two meteorites are in very close proximity to each other, they explode in a symmetrical way and create sound waves (that do not interfere with each other) My question is "Does the observer hear the two explosions at the same time,albeit at different pitches?" (I am asking this qustion in order to hopefully better understand the invariance of the speed of light , but first I need to understand this present situatio…

Will it crash? I think it will get smaller and smaller then explode.

Which principle may permit to store cryogenic liquids such as methane, hydrogen or nitrogen for almost indefinitely long time in liquid state without energy losses? For example there is such an effect: Could we create a dynamic localization in cryogenic liquids somehow?

This is not a perpetual motion proposal, on the contrary, is a machine that wears out of parts and has energy loses but like a car, it can be highly effecient due to a scheduled service plan. An alternator which has a hand lever to jump start it. The electric power generated by the alternator powers an electric motor which has a VSD (variable speed drive) connected to it. The machanical power generated by the motor is then delivered back to the alternator via a manual gearbox. Imagine, a bicycle. Replace the paddles with a motor which has a VSD, and the back wheel with a generator with gears on it. At first, the motor drives the alternator with with a small gea…

Does anybody know why an unifarmly charged sphere does not emite if its radius changed arbitrariby? It's known that accelarated charge emits but there is no radiation in my example. Any help here would be appreciated.

Leaving aside the practical challenges, of which there are many. I'd appreciate members' views on whether the basic physics of this concept holds water. Imagine a 20,000 km pipeline encircling Mars' equator. It's equipped with sunlight collectors and so forth sufficient to ensure that the daylit half contains water which freezes at dusk and remelts at dawn. Hence within the pipeline, we have two ice/water interfaces circling the planet at ~240 m/s, the equatorial rotational velocity. Due to the 8% expansion on freezing, 240 m of melting ice produces only 222 m of water, and on the other side of the planet, 222 m of water freezes into 240 m of ice each second. So…

An "Ice bomb" is made by filling a very strong iron container with water and freezing it. As water freezes it expands in volume exerting a force of some 100,000 pounds per square inch. The "ice bomb", usually a grenade shaped cast iron container, when frozen, will explode with tremendous force. If contained within a wooden box when it explodes, it will destroy the box. A conventional hot air or heat engine similarly utilizes the property of a gas that expands and exerts a force with a change in temperature. A gas is heated in a cylinder and the expanding gas expands and drives a piston. Could a thermal engine be constructed that utilizes the property o…

If you had a ball made of a material that could withstand any pressure, how much pressure would you need in the ball to make it so when you popped it the air would go near lightspeed?

Hello everybody. Is there anyone who can help me with a couple of questions about pressure, heat and the conservation of energy that have been niggling me for years? It all stems from when I first read Aesop's Fable about a man who confounds a Satyr by blowing on his hands to warm them up, and then paradoxically blows on his soup to cool it down. Both of the air flows begin their journey in the lungs with the same temperature and they travel the same route and distance, so the only variable appears to be the shape and size of the aperture; ie his lips. Reducing the size of the aperture increases the pressure and my understanding is that an increased pr…

Could somebody please explain the Archimedes principle All I really understand is that you split distance in half and never reach the designated spot btw I am 13 so Please Simplify it so I can under stand

I recently saw Big Hero 6 in theatres. One of the main heroes, Go Go Tomago, is working on a faster bicycle by using wheels suspended electromagnetically. Would such technology work in real life? I've seen it done before, but only in works of fiction.

Hi there science folks! I'm just your general layman who dabbles in sci-fi, and I'm having a bit of an issue that I was hoping you all could help with! Mind you, what I'm about to go over sounds off-kilter at the very least, but if you could at least entertain this as a thought experiment, I'd greatly appreciate it :) So I'm dealing with what I can only describe as a penetrating "disturbance" in my apartment. It travels up through the floor and causes different effects, from vibrating my legs, to causing me acute headaches, and other especially bizarre manners that leave me feeling molested. These occurrences only happen when I'm in my apartment, and due to covi…

Water and Antimony being the only two substances on earth that expand upon cooling, make them fascinating substances with very interesting roles both in nature and in man's industrial endeavors. If you have ever gone deep in tropical waters, you know that the warm blanket of water above keeps that water below cool. It floats up there like oil on water. If you go to the arctic, break through the ice, and go deep, you find 38 to 40 degree Fahrenheit water just under the ice, which may be -50 degrees on its surface. Ice is an excellent insulator. If water were not most dense in the 38 to 40-degree range, during the winter in the arctic, the night sky would absorb just …

This Mars-chopper is about 4 lbs in weight on Earth. How much bigger and more capable could a helicopter be on Mars? How long could the flight time be?