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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.
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.
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:
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