Physics

or any planet for that matter. i have been bugging myself with this question for days, please help with some physics input, the question is perhaps on theoretical physics but it bugs me nevertheless. Q. if we draw lines towards gravity of the earth, will the lines intersect at exactly one point at the center of the earth ? a plumbline would be such a line, if we have people holding a plumbline everywhere on earth, and someone draw an accurate line through it, would they all meet at one point ? i am trying to establish if gravity is a point, a singular point. many thanks for your ideas and input.

I've been trying to remember when I realised I don't actually know. A stream of electrons would be bent if it were to pass through a magnetic field, wouldn't it? So I don't think a magnetic field is actually made of electrons. I can only assume it's some force-carrier particle that I've forgotten exists. What is it and how are they generated?

How is this possible?

I have been wanting to learn more about circuits and how do design them. I have gathered so far that this comes under physics which is why I am posting this here. I would just like to know of any good books I could read and some of the math concepts and areas that designing a circuit involves. I have scoured the Internet trying to find some information on how you design a circuit but have found nothing. Thanks for your help.

I'm a student in grade 10, and i'm working on a science project. if i have a spherical liquid container made of an elastomer (rubber), can anybody tell me how to determine the thickness of the rubber which is needed to hold the liquid inside......just a general equation:confused: I need it so much.... Merged post follows: Consecutive posts mergedthis rubber container will carry crude oil inside it and it's made of an elastomer called Viton, only this high quality elasomer can resist the chemical components of the oil.....i want a general equation to determine the thickness of the container to be able to contain the oil according to the weight of the oil (quant…

This video shows a mechanism that appears to do a simerlar thing (I can't detemine from the video entirly how it works) to a powerball. http://www.youtube.com/watch?v=a49d5cJOGQ0&feature=channel_page When using my powerball it occured to me how efficent it was at converting human motion into rotation and I thought that it would be intresting to find out at what rate electrisity could be generated with one. The world record is to get one rotating at 16.5khz in speed. In the comments of the above video (in with all the crank comments) I saw a sugestion a bike could be made with this mechanism.

Ok this is most probably stupid but, if you where to heat a proton rich Environment to roughly the heat of the center of the sun or higher, confined the protons in a magnetic field that made sure they all stayed close together then put a small amount of anti protons into the middle of the protons would it create more anti protons than you started with. this is to simply discuss if you could create more anti protons than you started with using this method and weather the power requirement would be lower than using an atom smasher, this is not a discussion on the usefulness of antimatter, and if you wish to discuss that then say it after the yes or no so i can ignore it…

well, I was doing some homework and I was asked why the headlights of a car go dim when the starter motor is used somebody can explain me:rolleyes:??

Not sure if this belongs in chemistry or physics, but I figured it'd get more exposure here. In brief, my question is: what is the mechanism of radioactive contamination? Bit of context to what I mean, at a university in the UK there has recently been a controversy over the use of what was formerly Ernest Rutherford's lab. Several people working in the building have recently died from cancer, and there's fear it's still contaminated from his work. I'm familiar on a basic level with radioactivity, but it's not my specialty at all. How can radiation linger for nearly a century? My guess would be that nuclei in (for example) the walls, floor, etc. are converted t…

http://fantasticcontraption.com/

My son has a question for his science class and I am not knowledgable about the subject so I am looking for some help. Can a microscope make the beam from a laser more powerful?

if time slows at the speed of light, is this slowing relative or actual. If it's actual from the lights point of view it must not be travelling at the speed of light. So I presume it's relative, I would like to know thanks.

Is it possible to calculate the maximum height that you can dive or jump into a body of water without sustaining serious injury (or worse!!) ?

I am doing a science project on a homopolar motor and i have built a replica of the project shown in the video. however i do not know how to explain what is happening. Nor do i understand whats happening. Any help at all is much appreciated thank you in advance for all of your help

I need some help w/ this prob: A solid disk of mass 1.9kg and radius .05m rolls w/o slipping along a horizontal surface w/ a translational speed of .240 m/s. It comes to an incline that makes a 35 degree angle with the horizontal surface. Neglecting energy losses due to friction, to what height above the horizontal surface does the disk rise on the incline? So the problem gives me the following variables: mass:1.9kg r:.05m v:.240m/s angle:35degrees I'm not sure how to proceed though. What equation(s) should I use?

I need help determining whether or not a penny will stay on spinning disk (neglecting air resistance) given these variables: mass of penny: 2.5g distance from center: 10.0cm static friction: 0.19 angular velocity: 33.3rpm speed: 45.0rpm I'm not sure what equation(s) i should use so if you could tell me that would be a great help.

I'm thinking about cooling a non-flat surface; specifically a cylinder. The item in question gets too hot for simple air-based heat-sinking to be sufficient, so I'm toying with the idea of using a Peltier device to force-cool it. However, all the Peltier thermocooling units I've seen are essentially wafers. Are they ever found in other shapes? How simple would it be for me to construct one? (The materials, I mean, not the matter of machining it.) Thanks..

How can you calculate the thermionic work function of hydrogen? Thanks in advance.

Hi Guys. I'm newly joined, this forum looks great! I was reading through some exam papers from the state exams here in Ireland, and one of the questions was: I have to admit I'm curious and have been told there are numerous ways - can't think of any after two or three weeks. I know, that's pathetic! Any ideas? Warm Regards, Ed.

Hey guys! A quick question from a N00B to this site. Do objects in space have an electrical charge? Can particles from the sun or particles in general colliding with other matter create an electrical charge or electrical potential on the object their colliding with?

I had a thought and not sure if this is the section this goes in, but I'll post here. On some pieces of cardio equipment (bikes elipticals etc) you don't need to plug them in you are the power source for them. I wanted to know is there a way of taking the engery that one uses and converting it to usable energy that could be hooked up to the town or city provider? Thus giving energy back and possiably using to run your facility. Any ideas or comments? Thanks

This looks like quite an innovative new nuclear reactor: http://www.technologyreview.com/energy/22114/page1/ Apparently it needs very little U-235 and runs mostly on U-238. I don't keep up on nuclear physics very much so I am going with the information in the article to a large degree, but it sounds very promising. Does anyone know more about this technique? (also, if this post would be better elsewhere, please feel free to move)

I was thinking about roads being the energy supplier to a new-type of vehicle. If the streets can be made to absorb solar energy and transmit that energy to a new-type of vehicle, then a city can be energy efficient. A rode model to show a country how to be energy smart and clean. Any thoughts?

It's said that Rotation is when an [rigid] object turns about an internal axis e.g. a merry-go-round or gramophone record whereas Revolution is when an object turns about an external axis e.g. the Earth around the Sun. So why are gramophone record speeds given in terms of Revolutions Per Minute (RPM) and not Rotations Per Minute because the whole of the record is rotating about an internal axis?

could you have something like a fan, wich the propellers were connected to small generators, and theres also mini windmills on the blow-side wich take in energy from there too. would it make more than it used? it uses 2 energy supplies to make it, the mechanical energy of the fan blades moving, and the wind energy from the moving air. i think it might help if it was all in an airtight "shell" too. and if it could work then it could also be used in bigger curcamstances.