Physics

Hi. Creating this thread to not distort one related to a baseball and an arm... A crossbow of a given fixed force. An arrow reaches say 100 metres. A lighter arrow of same dimensions/aerodynamics will reach farther ? A heavier arrow of same dimensions/aerodynamics will reach farther ? (not about lethality/penetration on impact) For sure, an untralight arrow made of paper will not reach farther. For sure, a heavy arrow made of lead will not reach farther. How is its weight 'tuned' fox maximum flight distance ?

Man taking this Physics class.. I'm just loving every intricacy. There is a beauty I seen in it like no other comparable , when I'm learning Kinematics for the first time and I realize how I can describe motion mathematically, or the fashion in which the concepts of physics interpret the universe for the way she is as abstract as she is in an patternistic, simple, and proportional manner. I love how we take impossibly complex problems and solve them by breaking them down into simple kinematics. I'm definitely in the right science. The discipline of physics is so magnificently beautiful.

Hello: I am trying to determine the wet tensile strength for tissue fibers in units of pounds per ton. All I know is that a wet-strength resin is added to the tissue fibers and is present in an amount of at least 0.1 dry weight percent. Is there enough information to do this conversion? Or what other information would be required? Thanks in advance.

I have to also admit I've never taken Calculus level math. Though I'm concurrently going to take College Physics (Thank God I finally manage to take it) and Calculus 1 together. I'm a little worried, should I be? I've never taken a Calculus class and this will be my first Physics class.

Say a baseball weighs 150 grams. A pitcher can throw it about 80 metres away. If it was made 50 g lighter, would the pitcher reach farther ? If it was made 50 g heavier, would the pitcher reach farther ? For sure if the baseball was a 2 g paper ball, the pitcher would reach perhaps only 8 metres away. For sure if the baseball was a 5 Kg solid lead ball, the pitcher would reach perhaps only 8 metres away. How could a baseball weight be 'tuned' to reach farther, getting the most kinetic energy from a pitcher arm ? ... Or is it already weight-tuned as designed ?

i am interested in determining how strong the weak force is compared to the bigbang because i hypothesize that the weakforce is caused by an explosion. so where is the best place to get accurate data ill need about both of these occurances. and im curious if anybodies ever theorized the weakforce is an explosion. look forward to talking about this with you all.

So, assuming you have all the tools to contain and test it, what would be the outcome be if you put some alpha particles in direct contact with microwaves? would there be any transformation to more stable particles like an ion of He?

If you know everything about events leading up to a future occurance, then surely you can predict its outcome, does this mean that is outcome is predetermined. For example. In the lottery, if you knew the exact weight of the balls, the height they were dropped from, all of the coefficients of friction and all other information, e.g. air resistance etc. then surely you could program it into a computer and find the outcome. This Is already being done, to a certain extent with mapping weather systems in supercomputers. e.g. they predicted the effects of hurricane Katrina to a certain extent. If you had a powerful enough computer, and could program in sufficient information,…

Does Human Body sustain light speed vehicles? Now a says astrophysicist are trying to invent light speed vehicles for search of extra terrestrials.

I would think that snow boards are faster because they have a much larger over all surface area so the weight distribution would be a lot better so there would be less friction. this would be of cores a perfect run with the same steepness and no imperfection and it would not be groomed.

Hey everyone For an engineering project, I am trying to complete an electric circuit using salt water but I don't want to loose my electrodes from corrosion (allow electrolysis to occur)! is this possible? I was thinking of using AC circuit with high frequencies. I can change the type of salt in the electrolyte, the metals of the electrodes or the setup as you advice. Thank you ..

My questions mostly concern the history of physics. Who found the formula for kinetic energy [latex]E_k =\frac{1}{2}mv^{2}[/latex] and how was this formula actually discovered? I've recently watched Leonard Susskind's lecture where he proves that if you define kinetic and potential energy in this way, then you can show that the total energy is conserved. But that makes me wonder how anyone came to define kinetic energy in that way. My guess is that someone thought along the following lines: Energy is conserved, in the sense that when you lift something up you've done work, but when you let it go back down you're basically back where you started. So it seems…

Heavier, denser materials subject to thousands of years of pounding, grinding and swept by surf... Are they supposed to sink under the lighther silicate sands on a plain beach ? What minerals are typically supposed to lie under the beach sands, down to bedrock or down to whatever stops them from sinking further ?

Do magnets (permanent) become weaker as they are exposed to para-magnetic objects? I was thinking about this after seeing this. I am buying a magnet and wish to know if a magnet (permanent) loses its magnetic domain structure or alignment when exposed to para magnetic materials.

The earth accelerates towards perihelion and decelerates towards aphelion Furthermore it accelerates by full moon. How can these 2 factors be calculated, so that I for example is able to know the net result right now, or any given date / time

Hello, everyone. This will be my first post in these forums. I am a 23 years old student and I am starting my own business in the following 1-2 months. It will be an escape room. For those unfamiliar, here is a wiki page about this concept - http://en.wikipedia.org/wiki/Real-life_room_escape Essentially a group of persons (usually 2-4) enters a room (or1-3 room appartment) and they have to solve several intellectual, interesting and original tasks to get out of the room. Time limit is usually 60 minutes. I have thought of several tasks (such as finding coordinates where to put several mirrors, which when done correctly, redirect a laser beam, which opens a door to …

If the electric field and boundary conditions are known exactly for a region of space, is it true that there exists only one charge distribution in that region of space that could have produced it? My understanding of the uniqueness theorem in electrostatics is that for a given charge distribution and boundary conditions for a volume, there exists only one (unique) solution to Poisson's equation, and thus the electric field in that volume is uniquely determined. Does the arrow point the other way, too? If we know the field and boundary conditions, is the charge distribution uniquely determined in the volume? Is there a simple example that illustrates why or why not?

Weinberg-Witten theorem states that massless particles (either composite or elementary) with spin [latex]j > 1/2[/latex] cannot carry a Lorentz-covariant current, while massless particles with spin [latex]j > 1[/latex] cannot carry a Lorentz-covariant stress-energy. The theorem is usually interpreted to mean that the graviton ([latex]j = 2[/latex]) cannot be a composite particle in a relativistic quantum field theory. While the argument is so strong and weird, how is it possible? Why can we not construct a theory which is massless charged vector field and therefore carry a Lorentz-covariant current ? And although we assume the second argument is right, which sa…

When a ray of light is projected, (say) from the surface of Earth to outside in space. The condition is that, there is no obstruction to it till infinity (it travels only in vaccum). My question is that how far can that ray of light go? Also, instead of a ray of light, if I consider a beam of laser with same conditions, then how far can a beam of laser go? Compare both the situations. And does the light(ray of light and beam of laser) stops after traveling some distance or it has no end?

Do we know what energy is in Physics? I've thought about this for a long time, but it seems as though energy some what synonymous with motion and potential for motion. This my interpretation from my readings. Potential to do work. Though what causes an object to do work? What is it within the fabrics of that object that allows it do such a thing? Does this relate back to entropy and perhaps the big bang? It seems to me that energy comes from the instability of something to a more stable existence. Thus does this relate somehow to the big bang perhaps, how the general directionality of the universe is from unstable to more stable?

Here are the 2+1D gravitational Chern-Simons action of the connection [latex]\Gamma[/latex] or spin-connection: [latex]S=\int\Gamma\wedge\mathrm{d}\Gamma + \frac{2}{3}\Gamma\wedge\Gamma\wedge\Gamma \tag{1}[/latex] [latex]S=\int\omega\wedge\mathrm{d}\omega + \frac{2}{3}\omega\wedge\omega\wedge\omega \tag{2}[/latex] Usual Chern-Simons theory is said to be topological, since [latex]S=\int A\wedge\mathrm{d}A + \frac{2}{3}A\wedge A \wedge A[/latex] does not depend on the spacetime metric. (1) Are they topological or not? (2) Do they depend on the spacetime metric (the action including the integrand)? (3) Do we have topological gravitational Chern-Simons theory then…

Yes this is very true unfortunately, I've never in my life taken a physics course.

Could Cyclotron particle accelerator reaches over 120GeV of the ion's kinetic energy? If that cyclotron uses huge diameter of dees and very high frequency for dees. and even using multi-stage cyclotrons

Read somewhere many years ago, that any three of : Temperature, spark, fuel, oxygen Are needed to make fire. Is that imprecise/incorrect ?

Sooo a friend of mine had a couple questions in mind, if you guys have any possible answers, please do share, give us your thoughts 1- Can there be energy in 0 Kelvin? 2- Can 0 Kelvin exist in the universe? Answers appreciated in advance