Physics - June 2007

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2007-06-10 06:15:16 · 8 answers · asked by lin 1

What word goes in the blank? There's a word box with the following vocabulary listed in it so it muist be one of these words/phrases:
terminal velocity, net force, reduces, upward, acceleration, increases, kilograms, shape, gravitational, second, equal, atmosphere, air resistance, 9.8 m/s2, or moving object

2007-06-10 06:10:40 · 3 answers · asked by gabby 1

If a can begins empty, sitting at rest in a sea of pressurized air and the valve is opened, then what would happen to the can?
Wil the can move to the left, right, or not move once the valve is opened and air is let inside

Make the following assumptions: Pressure outside can = P ; mass of can = m; Area of can ends(each) = A; area of valve hole = s.

Newton's second law :

m*a = P*s*e^(-bt) - C*v(t)

a = d^2x / dt

v = dx / dt

m*d^2x / dt = P*s*e^(-bt) - C*dx / dt

m*d^2x / dt + C*dx / dt = P*s*e^(-bt) >>> Differential equation

the solution for this differential eq is:
y’ = Ps/(mb-c) { e^ (- c/m * t) - e^ (- bt)}

^^ according to this solution, which is velocity, the can will move to the right, but how can i prove that? we need to find something in common between all these relationships that prove it moves to the right.........

2007-06-10 06:04:42 · 2 answers · asked by Candy Cane 1

2007-06-10 05:47:07 · 2 answers · asked by Betty D 1

A 50 Kg man is on one edge of a 10 meter wood plank.
The wood rest on a frictionless ice through out its length.
The mass of wood is 20 Kg. It is homogeneous and uniform.
The man walk forwards the other end of the wood
How much is the distance walked by man with respect to the ground?

2007-06-10 05:32:59 · 14 answers · asked by CPUcate 6

I believe no. It could be tested with iron filings, and by looking at the field pattern the iron filing create. The pattern would be the same around the magnet.

2007-06-10 04:31:46 · 9 answers · asked by Kerri L B 1

2007-06-10 04:28:36 · 5 answers · asked by Arka Debnath 1

In other words, why is it they can beleive in 10 dimensional spaces....6 more than we're accustomed to....but HEAVEN couldn't possibly be one of those????

2007-06-10 03:47:23 · 9 answers · asked by bradxschuman 6

I saw a report yesterday on CNN that said they are so small that they can run to the edges on the inside and miss the waves. I don't care to try this, but I was wondering from all you science gurus if this is true, and if it is, could you please explain in plain english for all us non-science gurus how they can survive? Thanks, from a non-science gal.

2007-06-10 03:40:41 · 5 answers · asked by TotallylovesTodd! 4

what are the applications of uniform circular motion?

2007-06-10 03:40:38 · 4 answers · asked by kairrizordick 1

are there any new discovery using the principle of uniform circular motion?

2007-06-10 03:39:15 · 2 answers · asked by kairrizordick 1

like one large chunk of ice floating in a tub of water ,will the water level be higher or lower when the ice melts?

2007-06-10 03:27:20 · 5 answers · asked by Anonymous

Mercury?
Earth
please write the order including the new dwarft planets

2007-06-10 03:17:48 · 6 answers · asked by YA3200 1

2007-06-10 02:56:56 · 3 answers · asked by Anonymous

If a beam of light, for example sunlight or even a laser, is introduced into a closed loop of fiber optic cable, where there is no exit for the light, what would happen to it? Would the total length of the loop make a difference ie 3m of cable or 300km? Assuming total internal reflection would the light signal degrade and eventually stop?

2007-06-10 02:56:03 · 4 answers · asked by whandwhind 1

2007-06-10 02:50:29 · 7 answers · asked by Anonymous

1. Which of the following scientists inferred that an atom's positive charge must be clustered in the nucleus?
A) Niels Bohr
B) John Dalton
C) Ernest Rutherford
D) J.J. Thomson

2. In an atom, the number of protons equals the number of
A) Nuclei
B) Electrons
C) Neutrons
D) Isotopes

3. Elements in Group 17 (the halogens) are the _____ reactive metals.

4. Elements that form diatomic molecules, or molecules of 2 atoms each, are commonly found on the ____ right side of the periodic table.

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For questions 5-7, refer to http://www.corrosionsource.com/handbook/periodic/periodic_table.gif

5. List three elements from the group containing the most reactive nonmetals.

6. In each period, how does the number of electrons in each kind of atom change from left to right between Groups 1 and 2? Explain how you know.

7. How many atoms of a Group 17 elements would be needed to react with one atom of a Group 2 element? Explain.

-----------------

Thanks.

2007-06-10 02:41:18 · 4 answers · asked by angela 5

...how far does it travel in one second? I got 12.5 m, although I'm not sure if it's correct...

2007-06-10 02:35:28 · 3 answers · asked by Anonymous

2007-06-10 01:45:55 · 6 answers · asked by worried person 1

It's related to weight of the atmosphere per specific volume, and air pushes down on us, so i guess it does.

http://en.wikipedia.org/wiki/Atmospheric_pressure

2007-06-10 01:35:10 · 1 answers · asked by Roy Nicolas 5

could it tear space /time

2007-06-10 00:18:07 · 6 answers · asked by gasp 4

2007-06-09 23:34:55 · 5 answers · asked by Anonymous

2007-06-09 22:48:29 · 7 answers · asked by beygi 1

what are the units of efficiency?
and What is the SI unit if energy?

2007-06-09 22:46:56 · 5 answers · asked by ? 4

A uniform wire connected across a supply produces heat H per second.If the wire is cut into n equal parts and all the parts are connected in parallel across the same supply,the heat produced per second will be-
1. H\n^2
2. n^2H
3. nH
4. H\n

2007-06-09 22:42:53 · 5 answers · asked by godisgreat 1

When a battery sends current through a resistace R1 for time t,the heat produced in the resistor is Q.When the same battery sends current through another resistance R2 for time t,the heat produced in R2 is again Q.The internal resistance of battery is-
1. (R1R2\2)^1\2
2. R1R2^1\2
3. R1-R2\2
4. R1+R2\2

2007-06-09 22:37:10 · 1 answers · asked by godisgreat 1

A resistor R1 dissipates power P when connected to generator.If a resistor R2 is connected in series with R1 the power dissipated by R1-
1. increases
2. decreases
3. remains same
4. none of these

2007-06-09 22:26:35 · 5 answers · asked by godisgreat 1

Just wondering....cause that future in that movie seems so cool and more realistic than other futuristic movies...

2007-06-09 20:43:48 · 4 answers · asked by ExtmePillow 2

2007-06-09 20:43:40 · 3 answers · asked by Anonymous

What value would one measure friction using?
How do i work out this value in an experiment.

What graph would be most suitable to compare the friction of different substances?

2007-06-09 20:23:49 · 5 answers · asked by Rahhot 2