• Can a dog on a Tread Mill be used to power your Computer?

    Best answer: i dont think so but you can try it and see
    Best answer: i dont think so but you can try it and see
    10 answers · 11 hours ago
  • Is time travel possible?

    Do you think we will ever be able to do this?
    Do you think we will ever be able to do this?
    21 answers · 4 days ago
  • Does the past and future exist simultaneously with the present?

    Best answer: According to relativity theory, simultaneity of events are not absolute in the sense that there is a present moment that all observers agree on. Observers in relative motion do not agree on past, present and future. This is sometimes called Einstein's block universe (research it) In simplified terms, someone... show more
    Best answer: According to relativity theory, simultaneity of events are not absolute in the sense that there is a
    present moment that all observers agree on. Observers in relative motion do not agree on past,
    present and future. This is sometimes called Einstein's block universe (research it)

    In simplified terms, someone moving away from you experiences their present moment to be
    simultaneous with your past. For an observer moving towards you, their present will coincide
    with your future. The present is only simultaneous for observers between which there's no
    relative motion
    But for you, in your own reference frame, only your present moment exists, your past and
    future can only exist for other observers in their own reference frames. The question whether
    the past, present and future are simultaneous is up for interpretation. The entire Universe
    comprises a very large amount of different observers, can we have millions and billions of
    different past, present and future views for one subject? And yet any interpretation is real
    only for one single observer in that particular frame? That seems somewhat ptolemaic.
    The only safe conclusion we can draw from this is that time is not an absolute concept.
    7 answers · 1 day ago
  • If you shoot a bullet into the air, does it come back down?

    Best answer: Yes; of course and people do get killed from this sometimes. That's why it's not smart to shoot off guns in the air like you see sometimes in movies and television or sometimes will see at wedding celebrations in some of your countries in SWA.
    Best answer: Yes; of course and people do get killed from this sometimes. That's why it's not smart to shoot off guns in the air like you see sometimes in movies and television or sometimes will see at wedding celebrations in some of your countries in SWA.
    18 answers · 5 days ago
  • Why doesn’t the sun pull other objects than water?

    Best answer: The Sun's gravity pulls on everything. It's just that rocks and buildings are heavier and less likely to move the way that water does.
    Best answer: The Sun's gravity pulls on everything. It's just that rocks and buildings are heavier and less likely to move the way that water does.
    5 answers · 4 hours ago
  • Physics class is killing me :(?

    An owl is carrying a mouse to the chicks in its nest. It is 4.00 m west and 12.0 m above the center of the 30 cm diameter nest and is flying east at 2.50 m/s at an angle 32° below the horizontal when it accidentally drops the mouse. Will it fall into the nest? Find out by solving for the horizontal position of the... show more
    An owl is carrying a mouse to the chicks in its nest. It is 4.00 m west and 12.0 m above the center of the 30 cm diameter nest and is flying east at 2.50 m/s at an angle 32° below the horizontal when it accidentally drops the mouse. Will it fall into the nest? Find out by solving for the horizontal position of the mouse (measured from the point of release) when it has fallen the 12.0 m.
    9 answers · 5 days ago
  • Need help with physics/energy problem. Much Appreciated!!?

    Need help with physics/energy problem. Much Appreciated!!?

    Levers are a clever way of moving something heavy that you wouldn’t be able to move just by pushing on it. A lever consists of a “lever arm”, which is free to pivot about a point, or “fulcrum”. It relies on having the distance L1 be larger than L2. By pushing on the long arm, the force F1 you apply gets... show more
    Levers are a clever way of moving something heavy that you wouldn’t be able to move just by pushing on it. A lever consists of a “lever arm”, which is free to pivot about a point, or “fulcrum”. It relies on having the distance L1 be larger than L2. By pushing on the long arm, the force F1 you apply gets multiplied, and a much larger force F2 is applied to the load. At first glance, it seems like you get “something for nothing” when using a lever; you apply a small force, and you’re able to move an object with a much larger force! On closer inspection, it turns out not to be so; the work done on the object matches exactly the work you put in. Here, we will derive the basic lever equation F1/F2 = L2/L1 Part 1 If you push the long end of the lever down a distance d1, how much does the other end move up? (Call this distance d2.) Express you answer in terms of L1 and L2. Part 2 Assume that the work you do is equal the work done on the load. Express this assumption in terms of the forces F1 and F2 and displacements d1 and d2, and use your answer from part 1 to derive the lever equation. Part 3 (you can do this part without doing part 1 or 2) If I gave you a lever arm 10 m long, where would you have to rest it on the fulcrum to lift a 1000 kg object off the ground? (I.e., what must the ratio L1/L2 be?) (Hint: The force you can exert is probably largest if you lean on it and push down with all your weight.)
    7 answers · 4 days ago
  • Professor Stephen Hawking has passed away at the age of 76?

    Best answer: When I was 5 my mom read me George’s Secret Key to the Universe, that book shaped my earliest years, making me obsessed with being as smart as Stephen Hawking. Thank you Mr. Hawking, and I’m so sorry Lucy Hawking for your loss.
    Best answer: When I was 5 my mom read me George’s Secret Key to the Universe, that book shaped my earliest years, making me obsessed with being as smart as Stephen Hawking. Thank you Mr. Hawking, and I’m so sorry Lucy Hawking for your loss.
    7 answers · 4 days ago
  • Explain to a dummy "photons have mass and at rest that mass is zero". That whole bit about mass converting to energy, but not the opposite?

    Best answer: I'll start with the conventional thought first; then add some more recent ideas just to whet your appetite. First, in conventional or classic physics we say that photons have no rest mass m. But they do have measurable momentum P = E/c = hF/c where F is the photon's energy and h is a constant. And, yes,... show more
    Best answer: I'll start with the conventional thought first; then add some more recent ideas just to whet your appetite.

    First, in conventional or classic physics we say that photons have no rest mass m. But they do have measurable momentum P = E/c = hF/c where F is the photon's energy and h is a constant. And, yes, photons do have momentum, it's been measured, and no they have no rest mass...according to conventional generally accepted models.

    Most recently a few physicists have been toying with the concept that photons actually have a very very very ... very tiny bit of rest mass. I've forgotten the actual number but it has lots of zeros in front of it. But if this be true, what does that do to the idea that only massless things can go the speed of light?

    Which brings us to the energy.mass equivalency thing, e = mc^2. The whole equation is actually E^2 = e^2 + k^2; where E = Mc^2, e = mc^2, and k = Mvc and M = m/sqrt(1 - (v/c)^2) is the relativistic inertia of the rest mass m moving at the speed v. k is the kinetic energy (the moving energy) of the rest mass m as its inertia swells to M > m.

    The m is the rest mass of any sub atomic particle (SAP). So when that SAP is a photon and its rest mass m = 0, we have E = k = Mvc = Mc^2 = hF = Pc; so that P = hF/c is a photon's momentum and that agrees with experimental results. In short e = mc^2 does not apply to photons (in the conventional model).

    And to your point e = mc^2 for particles with rest mass, m = e/c^2 is a perfectly legit relationship. That is, under special (laboratory) conditions they in fact have created rest mass m from energy e. But it takes loads of energy just to make the mass of one tiny SAP about the size of a meson for example.
    5 answers · 3 days ago
  • How are things waves?

    Best answer: Classically, light is a combined wave in an electric field and a magnetic field where essentially the motion in each field causes motion in the other. it is a sort of self perpetuating pair of waves that can travel indefinitely in a vacuum until they encounter matter. The whole wave / particle quantum business is... show more
    Best answer: Classically, light is a combined wave in an electric field and a magnetic field where essentially the motion in each field causes motion in the other. it is a sort of self perpetuating pair of waves that can travel indefinitely in a vacuum until they encounter matter.

    The whole wave / particle quantum business is a different more fundamental model of light from which the classical view emerges at larger scales. It is pointless to try and explain quantum theory in a few lines but the wave part more or less describes the probability of where a particle could be and the particle part is that ultimately a particle of light will turn up in random a location determined by the probability wave. The medium for the probability wave of light seems to be just space itself (or spacetime).
    5 answers · 4 days ago
  • Does filling a room with water vapor increase the air pressure in the room?

    Best answer: The partial pressure of one gas adds to that of the other. So the pressure would increase if all other factors were kept constant. Now the act of evaporating the water LOWERS the temperature so unless HEAT was added through the walls the air would tend to shrink. But if it remained at the same temperature and it... show more
    Best answer: The partial pressure of one gas adds to that of the other. So the pressure would increase if all other factors were kept constant.
    Now the act of evaporating the water LOWERS the temperature so unless HEAT was added through the walls the air would tend to shrink.
    But if it remained at the same temperature and it was sealed then the pressure increases by the partial pressure of water at that temperature.

    I should add that this is how clothes dry on the clothesline. The evaporating water increases the local pressure slightly so the moist air moves outwards from the clothes. The water diffuses outwards even in the absence of any wind or other air current.

    For example at boiling point the partial pressure of water is 1 atmosphere. It is capable of pushing the atmosphere out of the way. That is what boiling means.
    So if your container had both air and water the pressure could rise substantially higher than if the container had ONLY water vapour in it.

    PS the reverse is true. If you boil the water and exclude the air, then seal the container and let it cool, the pressure drops to ONLY the partial pressure of the water.
    This is much less than atmospheric. So a weak container crushes.

    A stronger container keeps the water at "boiling point" at all times.
    The slightest heat on the water makes it immediately boil.
    Put a glass container like this in your hand and watch the water boil at skin temperature.

    Fun
    6 answers · 5 days ago
  • Why doesn't a plane traveling against the rotation of the earth arrive at its destination faster than if it were to rotate with it?

    I need a simple explanation please!
    I need a simple explanation please!
    8 answers · 5 days ago
  • Why doesn’t Trump ask Putin about Uranium One?

    He clearly trusts Putin. Why not just ask?
    He clearly trusts Putin. Why not just ask?
    4 answers · 5 days ago