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最佳解答74%
解答2,534
  • A tripod lands on a plane?

    A tripod lands on a plane a fixed number of times

    such that the distance between vertices is always

    s1=6m,s2=7m,s3=8m,s4=9m,s5=10m,s6=12m. What is

    the maximum mass of water possible iff distinct

    volumes are allowed? rho=1000 kg/m^3

    Happy New Year Earth.

    1 個解答Physics6 年前
  • REPOST: There are two isolated points?

    There are two isolated points where

    f(x,y)=5y^2 + 15x^2 - 60x^3y + 15xy - 30xy^3 - 30x^4 - 60x^2y^2 - 6y^4=k

    where k=25/24 indeed. What are the coordinates of these two points.

    Happy Halloween weekend.

    2 個解答Physics8 年前
  • 24 hour clock problem?

    A vehicle using a 24 clock will maximize distance after

    occurrences of time, (h+m+s)s accumulate, and constant

    speed then after is also given by (h+m+s) m/s.

    At what time does the trip end and how far did it

    travel? Time starts at 00:00:00.

    2 個解答Physics8 年前
  • Super drat or just a matter of physics?

    On a planet the size of earth a drat moves 100m

    south, 100m east, 100m north, and ends up where he

    (or she) started. Thinking out of the box, how did this in

    fact happen, and what is the subtended angle

    More details:

    The drat is very confused. This keeps happening no matter

    where he is on the planet. Spherical polar coordinate systems

    do not exist relative to the drat.

    Radius of earth 6378 km

    The north pole does not exist.

    The triangle like path is composed of

    three arcs. There is no planetary dipole

    magnetic field. This question is related

    to a contact's now deleted question.

    Actually, Anthony Hopkins had a similar problem;

    he ended up where he started.

    2 個解答Physics9 年前
  • How does your mind work?

    After enough practice, many of us simply know answers to problems,

    but do you have some idea about how your unique mind prepares to

    analyze problems in math, physics, or anything for that matter.

    In other words, how would you describe the preparatory inner workings of your mind?

    For instance, do you use visual, audio, or some unique combination of things

    during preparation for analysis. Please watch the videos below before answering.

    There is no right or wrong answer so please feel free to

    answer anyway you want. Thank you.

    http://www.youtube.com/watch?v=gBEMvE_7meo&feature...

    http://www.youtube.com/watch?v=KPxybWtz8zE&feature...

    1 個解答Physics9 年前
  • Simple EPR paradox #1?

    Jack and Jill set up their particle polarization or spin detectors with symmetry in three

    dimensional space. Midway between these locations particle pair production occurs.

    These particles travel directly to said detectors. What is the probability that Jack will

    correctly forecast Jill's result and vice versa according to expected experimental(s)?

    Thank you.

    1 個解答Physics9 年前
  • How long does Joe's trip last?

    Joe the flying ant loves to run the rim of a hollow

    cylinder at 12 m/s. After running from point (A), he decides

    to fly at 3i m/s parallel to diametrically opposite point (B), but

    he doesn't realize that his flight path (plane) is falling at rate

    (g). So he ends up banging his head into the wall at point (B') directly

    below (B). What is the maximum amount of time it takes Joe

    to go from (A) to (B) if Joe, now dizzy, walks from B' to B at

    2 m/s due to the lump on his head, and what unsimplified *physical *

    equation represents his actual path? Thank you.

    2 個解答Physics9 年前
  • How might Dr.Feynman intuitively explain time dilation?

    How might the great Dr.Feynman explain proper time dilation of a

    macroscopic object during a (real) round trip where it lands on

    a hypothetical planet orbiting Proxima Centauri (4LY) and then returns

    to earth in the most intuitive (simple) way? I'm asking on behalf of

    a contact.

    Respectfully, do not answer using arguments like

    "space-time rotation matrices", "twin paradox", and

    the like unless if is flat-out intuitive. I can envision

    how he might do this. If said explanation exists, please

    include it. As best I can tell, he always had a beautiful

    simple way of explaining things like this.

    4 個解答Physics9 年前
  • Puzzling violation of relativity?

    Steve is upset because he has no

    coffee with his breakfast so his

    wife says: "Take off and buy some."

    Off he goes lickity split in his space

    plane at 0.99999c to a well known coffee

    bean planet (4LY) orbiting proxima centauri

    that sells coffee. Coffee beans are extinct

    on earth due to GW. When he gets back he

    makes some coffee and continues eating breakfast

    with his family. He went into the past.

    Was Einstein wrong?

    4 個解答Physics9 年前
  • It is nice to go fishing again?

    A shark in the ocean, initially hanging motionless on a spring scale

    is suddenly whacked by a meteorite of equal mass. The resulting

    motion of the shark is given by: f(t)=e^(-[π/200]t)sin( [(a+b]/a)/8] * t) = δ(t)

    where a / b = (a+b) / a and (a,b) are segments of a straight line.

    What is the mass of the meteorite?

    Thank you.

    1 個解答Physics10 年前
  • A ball floating in the ocean : reinstate?

    A ball is floating in the ocean at latitudes south

    of 60 degree south latitude. What is the density of the

    ball? calculus or geometry derivation ok.

    Thank you.

    5 個解答Physics10 年前
  • What is the distance in meters?

    Derive the distance between protons in a

    hydrogen molecule (revist)?

    Data:

    k = 1 / 4πeo

    m = 9.106E-31 kg

    q = 1.602E-19 C

    ħ

    2 個解答Physics1 十年前
  • Simple or hard thermodynamics?

    What is the current effective BB thermal resistance of

    air, and approximately how many d=100m ponderable

    hydrophobic polystyrene balls (reflectivity=95%) do

    I need to float on the ocean to lower the annual mean

    surface temperature of earth by 1°C.

    4 個解答Physics1 十年前
  • A photon is sent directly from a hydrogen atom?

    A photon is sent directly from a hydrogen atom on earth to a solid

    sphere of uniform density at rest at the top of an inclined plane

    plane. Consequently, the sphere rolls down the rigid incline without

    loss. After collision, a single photon is emitted. Said photon

    is absorbed by the same hydrogen atom on earth. How much time

    has elapsed relative to an observer next to the atom?

    Notes: my thought experiment: 1/1/2011

    Assume equipotentials for atom, Sirius, and incline remain constant.

    http://i985.photobucket.com/albums/ae336/sdopqwe82...

    2 個解答Physics1 十年前
  • A twenty four hour clock has metric?

    A 24 hour clock has metric ds^2=r^2dΦ^2+dr^2 where r=4Φ and

    marks time every half-hour What is the total distance traveled

    during odd intervals?

    1 個解答Physics1 十年前
  • Easy fluid mechanics problem?

    The planet mercury has been turned into mercury with the

    uniform denstiy (p) of liquid mercury. An alien pentagonal

    obelisk (density=p/3) containing a message for earth remains

    at rest near mercury's center until equilibrium is reached at which

    time it moves along the radial coordinate without frictional head.

    In order to reach Earth, the oblisk must reach escape velocity.

    Does the obelisk reach Earth?

    Data planet

    No thermo.

    elastic modulus = 3 * 10 ^ 9 N/m^2

    p = 13570 kg/m^3

    Data obelisk:

    h1 = 10m (body)

    h2 = 1m

    edge=1 m

    2 個解答Physics1 十年前
  • Simple math question?

    A regular 4-gon has a perimeter of 100 meters?

    A similar "physical" 4-gon has a perimeter 97.0882063242942 m

    The formula for the physical 4-gon is?

    Each "conner" has a different radius of

    curvature based on a mathematical constant.

    ref:

    http://answers.yahoo.com/question/index;_ylt=ApeQ7...

    2 個解答Mathematics1 十年前
  • How high does the teeny tiny shell rocket fly?

    A hemisphere shell with mass m and radius R rests on a horizontal table. At the top of the shell there is a hole. The shell is filled with a liquid with density=ρ up to height h<R, The air has density ρ_a=constant. How high (h) does the rocket fly?

    Solve this problem using spherical coordinates and

    the concept of hydrostatic flux density.

    Bonus: What percentage of the water's energy

    was imparted to the shell?

    3 個解答Physics1 十年前
  • A drat races a 3 sided coin rematch!?

    A solid spherical drat of mass m radius r where g'=0.5g

    races a solid "3 sided coin" of mass m radius r and of length

    equal to 4r where g'=3g start rolling down the same incline at the

    same time.

    And the winner is?

    1 個解答Physics1 十年前
  • A strange grass satellite is orbiting Rigel?

    A strange grass satellite orbiting Rigel at 7 AU

    contains 1k diatomic molecules with energy

    levels separated by 4m^-1. How many

    are in the 3rd state.

    Temperature Rigel = 11000K

    Radius Rigel = 62*solar radius

    1 個解答Physics1 十年前