Physics - December 2007

Hey can someone help me to solve this problem? The question is if an incline has a ideal mechanical advantage of 4 and the pyramid is 15 meters tall, how much of an angle would a worker have the incline in order for him to reach the top. I cant seem to wrap my head around it :( any help would be appreciated.

2007-12-25 08:14:59 · 4 answers · asked by RICARDO S 2

Did I just make this up? It was a long time about but I think it was a drummer for Poco, and there was speculation that he may have been killed because of some sort of classified information he had about "gravity waves" whatever those are.

2007-12-25 07:53:25 · 4 answers · asked by DeFreeze 4

Suppose that a binary star system consists of two stars of equal mass. They are observed to be separated by 370 million kilometers and take 6.0 Earth years to orbit about a point midway between them. What is the mass of each?
answer is in kg

2007-12-25 06:38:48 · 2 answers · asked by hermionegranger 2

A glass of neglible heat capacity contains 100g of water at 20 degrees celsius
a) how many mlecules of water are inside the glass?
b) what mass of ice at -20 degrees celsius should be added to water to cool it down to 10 degrees celsius?

2007-12-25 06:37:48 · 7 answers · asked by Anonymous

Prove that in the elastic collision of two objects of identical mass, with one being a target initially at rest, the angle between their final velocity vectors is always 90 degrees.

2007-12-25 06:14:21 · 6 answers · asked by mn_mikaelian 2

Please explain wich are the most usuals, and wich are best payed. Also, please try to explains what the job concists of.
Thanks a lot!

2007-12-25 05:40:27 · 2 answers · asked by Sebolains 2

2007-12-25 05:22:09 · 1 answers · asked by AquarianChalice 1

Two loudspeakers are 1.00m apart. A person stands 4.00m from one speaker. How far must this person stand from the second speaker in order to detect destructive interference when the speakers emit a 1150Hz sound? Assume the speed of sound in air is 343 m/s.

2007-12-25 05:18:01 · 5 answers · asked by Mykill J 1

2007-12-25 04:33:50 · 12 answers · asked by ankit 1

I'm wondering what effect the iron-ore taken from Iron moutain,Minnesota has on the rotation and also all the weight of what has been sent out into space has.And what was the total weight of the iron-ore?

2007-12-25 03:36:10 · 8 answers · asked by doctorwaterbed 1

2007-12-25 03:13:05 · 3 answers · asked by Allergic To Eggs 6

2007-12-25 02:04:46 · 15 answers · asked by Anonymous

2007-12-25 02:02:18 · 34 answers · asked by Anonymous

birth..rage seperated from myself..use life to attempt to MERGE again too myself using ma-other single-unique-thing as the food for hungry and finding war ..only on wienner ahh winner now consume control purpose safety ill lusion...next

2007-12-25 00:17:48 · 3 answers · asked by WordBarker/singlething 2

....and the angle seperating its source from the target?

I remember such a thing from my physics courses, it had a shape similar to Y = A *sin x and was useful to understand engines.

2007-12-24 23:58:04 · 4 answers · asked by Roy Nicolas 5

2007-12-24 23:36:39 · 5 answers · asked by Anonymous

2007-12-24 21:55:36 · 3 answers · asked by Anonymous

A circular pond of radius 12 m has a layer of ice 0.25 m thick. On a spring day, the temperature of the water below the ice is 4.0°C and the temperature of the air above is 11°C. What is the rate of heat transfer through the ice, in kW?


- The thermal conductivity of air k (W/mK) is 0.025 , and its thermal resistance RSI-value (m2 x K/W) (for 1 inch) is 1.00 and R-value (ft2 x F° x h/Btu) is 5.70.
- The thermal conductivity of water k (W/mK) is 0.598, and its thermal resistance RSI-value (m2 x K/W) (for 1 inch) is 0.04 and R-value (ft2 x F° x h/Btu) 0.24.
- The thermal conductivity of 0° C ice k (W/mK) is 2.14 , and its thermal resistance RSI-value (m2 x K/W) (for 1 inch) is 0.01 and R-value (ft2 x F° x h/Btu) 0.07.
-These values are at 10^5 Pa, 20°C.


Thus far, my answer of 25 kW was incorrect, help please?

2007-12-24 20:44:54 · 3 answers · asked by Xar 1

2007-12-24 19:52:42 · 6 answers · asked by Anonymous

Why is it that when ever the years move on, it seems like it moves faster and faster? I mean when I was about 12 years old, time moved so dang slowly as I kept watchin the clocks go waiting for class to end, but now, I'm fifteen, and months are passing by like pilots smashing down on the afterburner.

2007-12-24 17:06:53 · 11 answers · asked by Ren 3

2007-12-24 17:03:32 · 5 answers · asked by Micheala #1 Fan of WDPLM-2 4

A light source, S, is located 2.0m below the surface of a swimming pool and 1.5m from one edge of the pool. The pool is filled to the top with water.
a) At what angle does the light reaching the edge of the pool leave the water?
b) Does this cause the light viewed from this angle to appear deeper or shallower than it actually is?

2007-12-24 14:44:36 · 2 answers · asked by david 2

Hawking or Susskind? Not saying that either one of them have it right, at this time but that more info will come over time. But which one seems to have a better handle on it at this time?

2007-12-24 13:22:29 · 1 answers · asked by Anonymous

*Not invented by me.

First was nothing.
A fold in the void separates fullness of nothing, and absence of fullness.
Which are the same in essence but opposed.
Thus the first pair of poles was made.
Fullness of nothing was on top,
Nothingness of something under.
By that occasion the void splits again.
It is at the same time definite
And not definite.
On one side goes definition and on the other, non definition.
This feeds again the opposition between fullness and nothingness, since we now have 4 parts in the void.
And, this indicates an evolution.
A change.
A flow.
The flow itself is an entity feeding the pole of fullness.
A succession of other folds are drawn in the void,
until the potential at the poles is big enough to shape a wave.
Which is not yet matter.
The wave is an entity and again feed the primal pole of fullness.
Many waves cumulate until they build a charge.
And light is made from that charge.
Again two new entities light and charge feed the poles.

2007-12-24 13:17:12 · 11 answers · asked by Roy Nicolas 5

2007-12-24 12:59:19 · 6 answers · asked by missakel 1

2007-12-24 12:52:04 · 6 answers · asked by Anonymous

When you leave your balloon out, say in your bedroom, for a few days (not a helium balloon), why does it lose its air?

2007-12-24 12:31:10 · 9 answers · asked by Anonymous

Situation: There are two blackholes; one that was formed completely of matter; and on that was completely formed of anti-matter. Do they cancel each other out and form energy or just make a bigger blackhole? (Maybe I just shouldn't have started reading science fiction again!)

2007-12-24 11:18:46 · 9 answers · asked by Anonymous

a) a pump is is used to move water through a short pipe of diametre 100 mm. The water has a temperature of 15 ͦ C and a pressure of 100kpa. The pump moves the water up a vertical distance of 2m and the water exits to atmospheric pressure. Assume the process is adiabatic and frictionless. If the mass flow rate of the water is required to be 3kg/s, calculate the power required by the pump.

b)how would introduce the effects of friction into the problem described?

Any help would be most appreciated
Thanks!

2007-12-24 10:55:22 · 2 answers · asked by Anonymous

You’re sitting on the subway with a cup of coffee on the floor. It never seems to fall, despite the large accelerations and decelerations that the train makes. With what magnitude must the train accelerate (or decelerate) in order to make the cup topple over. Assume that friction is strong enough that the cup does not slide, it just falls. You can think of the cup as an ideal cylinder, full to the brim with coffee that has the same density as water. The dimensions of this perfectly cylindrical cup are diameter = 5cm and height = 12cm.
It will be very difficult to find an exact number for this acceleration, though there is most certainly a distinct number that if the train reaches, the coffee will spill. You do not have to find the exact number, just list steps to solve it.

2007-12-24 10:02:07 · 3 answers · asked by Patrick 1