A high school kicker makes a 34.0yd field goal attempt (in American football) and hits the crossbar at a height of 12.0ft .

What is the magnitude of the net displacement of the football from the time it leaves the ground until it hits the crossbar?

What is the direction of the net displacement of the football from the time it leaves the ground until it hits the crossbar?

Assuming the football took 2.70s to hit the crossbar, what was the magnitude of its average velocity?

What was the direction of its average velocity?

Explain why you cannot determine its average speed from these data.

I recently bought some buckyballs, considered to be the world's best selling desk toy. Essentially, they are little, spherical magnets that can form interesting shapes when a bunch of them are used together.

After playing around with these buckyballs for a while, I wondered: "Can these guys ever lose their magnetism?" Then I went a step further and thought, "How are magnets affected by the 2nd law of thermodynamics?"

So, how are magnets affected by the 2nd law of thermodynamics? Do they break down and lose their magnetism over time (like iron rusts over time)?

Assume a length of axon membrane of about 0.10 m is excited by an action potential (length excited = nerve speed

Given a stream of random binary numbers(*)

Is there any way to differentiate if they came from a Truly Random or from a formula/algorithm ? how?

if there is no way to decide this, then, I can't find any basis, to keep denying that behind the "truly random" of quantum mechanics can be a hidden algorithm.

I know I am talking about the posibility of a "hidden variables" theory, but I can't find any other explanation.

(*) Is known that is possible to create computable normal numbers from which first is possible to extract an infinite random binary stream, second, it tell us that a finite logic expression (again a binary stream) can contain a rational, and even an irrational number, so there is no big difference within a bit stream and the measurement of a random outcome, (and even less if we consider the accuracy) I say this, because the argument that obtaining bits is not the same as answer the complex question that can be made to quantum experiments, I think that "random" results can be perfectly read from a random stream of bits

A wire coil of 35 turns has a cross-sectional area of 12 cm2. The coil is placed in a uniform field of a large magnet with B = 0.32 T. The coil is suddenly rotated 90 o from an orientation parallel to the field to one perpendicular to the field. The time to flip the coil is 0.47 s. What is the magnitude of the average emf produced?

What will be the average current produced if the circuit of the coil is closed and the resistance is 80 ohm?

I would like to test my hardware under vibration that can appear on a highway gantry. If someone has a model of such vibration. i.e period and amplitude.

In my lab I have a motor that can be regulated according to its RPM.

According to Rindler the geodetic effect can be considered as consisting of Thomas precession combined with the effect of moving through curved space.

Wolfgang Rindler (2006) Relativity: special, general, and cosmological (2nd Ed.) p234

However according to Misner, Thorne, and Wheeler, Gravitation, p. 1118, Thomas precession does not come into play for a freely moving satellite.

See: http://en.wikipedia.org/wiki/Talk:Geodetic_effect

I think that although a freely moving satellite doesn't feel gravity, it's relation to an observer is still subject to lorentz transformations and hence Thomas precesssion.

So who is right ? Rindler or Misner, Thorne, and Wheeler ?

Every orbiting of a satellite around a mass is nothing else but a constant fall - and therefore acceleration - towards this mass. In a way it is a "falling around" that mass.

My question
Is it possible to measure this acceleration on earth due to its "falling around" the sun?

Say you have a chemical compound made up of one or more radioactive nuclei. If the nucleus decays, does the compound?

Possible outcomes I can think of:

the compounds continues to exist if a bonding is still possible between the decay product and the rest of the original compound.

the compound just ceases to exist.

the decay product forms a new compound with some fraction of the remainder of the original one but discards some other part.

Generally, it will do whatever results in the least energetic state, but is there some kind of regularity to it?

I find plane waves are uncompatible with light cone.

Perhaps plane waves are "virtual" and can never be measured in that case, shouldn't we call plane waves as "virtual plane waves"? (other option could be that plane waves allows waves travel faster than c)

I would like to clarify this point through this question.

If plane waves would exist(as measurable), then higher than c speed could be reached like this:

A wave going from X to Y at a speed c, it will reach Z at higher than c speed, because it will reach at same time, traveling more distance.

(X).
|   
v   
________________________________________________
plane waves ________________________________________________
going X to Y ________________________________________________
(Y). (Z).

In a real situation the wave will be a circle (or a sphere in 3d) so it will get Z later then that's not a plane wave.

The other three forces' mediating particles (photons etc.) are absorbed by their appropriate charge-carrying particles, but I can't seem to find a clear answer that applies to the gravitational force in a quantified scenario.

The different answers to this most basis question seem to elude me in frameworks of String theory and LQG, though it becomes more intuitive in the latter

A water pipe having a 2.55 cm inside diameter carries water into the basement of a house at a speed of 0.760 m/s and a pressure of 237 kPa. If the pipe tapers to 1.56 cm and rises to the second floor 6.04 m above the input point, what are the (a) speed and (b) water pressure at the second floor?

Please Explain. Thanks!

Two very large parallel sheets are 5.00 cm apart. Sheet A carries a uniform surface charge density of -8.30?C/m2 , and sheet B, which is to the right of A, carries a uniform charge of 12.2?C/m2 . Assume the sheets are large enough to be treated as infinite.

Find the magnitude of the net electric field these sheets produce at a point 4.00 cm to the right of sheet A.

Find the magnitude of the net electric field these sheets produce at a point 4.00 cm to the left of sheet A.

Find the magnitude of the net electric field these sheets produce at a point 4.00 cm to the right of sheet B.

Three children, each of weight 361 N, make a log raft by lashing together logs of diameter 0.21 m and length 1.60 m. How many logs will be needed to keep them afloat in fresh water? Take the density of the logs to be 800 kg/m³.

Laser beams are said to have high "spatial coherence". This means that the beam is highly concentrated even at long distances (low spread).

Can this be achieved with radio waves (much longer waves) or is it due to laser's stimulated emission?