Physics - May 2007

If so, why?

2007-05-14 07:45:21 · 7 answers · asked by Isabelle06 4

2007-05-14 07:32:50 · 12 answers · asked by that guy 1

Hello,

I have got a following physics problem.

A dumbbell (distance between balls is l) stands upright on a flat. This dumbbell is released to move. What speed will have each ball when the dumbbell hits the flat (there is no friction).

I thinks that here should be used energy and angular momentum conservation laws, but I have now idea how to use these equations.

Has anybody any ideas how to solve it?

2007-05-14 07:04:54 · 3 answers · asked by Pythagor 1

2007-05-14 07:01:14 · 4 answers · asked by Binx 1

I am looking for some ideas on this that do not rely on "because e=mc2" or because you would become infinitely or need infinite energy. What is it about the speed of light that makes it special. Would the speed of light be different if some other fundamental aspect of the universe were different. Don`t give me any equations because I won`t understand them.

2007-05-14 06:53:06 · 10 answers · asked by Anonymous

2007-05-14 06:47:48 · 8 answers · asked by Alexander 6

A brass ring of diameter 10.00 cm at 19.0°C is heated and slipped over an aluminum rod with a diameter of 10.01 cm at 19.0°C. Assuming the average coefficients of linear expansion are constant.
(a) To what temperature must this combination be cooled to separate the two metals?
______°C
Is this temperature attainable?
___no
___yes
(b) To what temperature must this combination be cooled to separate the two metals if the aluminium rod were 10.05 cm in diameter?
______°C

2007-05-14 06:28:26 · 1 answers · asked by Emma 1

2007-05-14 06:07:12 · 6 answers · asked by kellie h 1

2007-05-14 06:04:19 · 11 answers · asked by sciwiz2010 1

2007-05-14 05:41:50 · 5 answers · asked by pscosty 1

This is my GCSE science work, I looked all over the internet, but can't find information on this topic, are there any sites out there, which have pictures of circuits with two transistors.

2007-05-14 05:30:41 · 2 answers · asked by Anonymous

2007-05-14 05:22:16 · 1 answers · asked by heguy 2

On Mythbusters I've seen them attach stickers to measure the g-forces that an object experiences. Who sells these, what are the available "g force ratings" and how much do they cost?

Are the stickers "directional"? Do I need to afix them in the X, Y and Z directions? Or will the internal media change regardless of the force's direction?

For my application I only need a low g-rating -- nothing extreme.

If you have experience with these stickers, please share your comments or suggestions. Thanks for your help.

2007-05-14 05:14:38 · 1 answers · asked by Anonymous

If an object or person is traveling at the speed of light past a mirror, will there be a reflection for a nearby person to see? What about if the object is traveling faster than light speed? Will there be no reflection? Will it be delayed? Will it just be to quick for a person to see?

2007-05-14 04:57:04 · 9 answers · asked by Julie K 1

a) Magnitude of Force
b) Nature of Force (tension or compression)
c) Comment on any differences between the two answers.

The triangle (not right angle) has a force bearing down on the top of 8.8kN and 4.1kn and 4.7kN forcing up on either side. It is 38 degrees the left hand corner and 41.85 degrees on the other.

Cheers

2007-05-14 04:55:55 · 1 answers · asked by Pickled 1

Two coaxial rings of diameter c = 5cm are connected
by thin soap film. Diameter of narrow neck of the
film is a = 4cm.

What is distance b between the rings measured along
the film (as ant travels)?

2007-05-14 04:14:28 · 1 answers · asked by Alexander 6

I need to create a mathematical model where are two rockets: one with two stages and the other with one stage. At the beginning, each rocket has got the same amount of fuel.
I have to compute how many times bigger speed can reach a two-stage rocket than one-stage rocket?

Has anybody some ideas about it? Maybe there are some internet links where I could find this model?

Thanks in advance.

2007-05-14 04:11:14 · 1 answers · asked by Pythagor 1

ie:i use 15w cfl to lightup my room ,can i use a led kind of light to get the same lumens ,then will it effect my eyes .

2007-05-14 03:52:19 · 2 answers · asked by Abdul kareem 1

what is the wavelength of these sound waves?
(b) The sound waves emitted by the bat are reflected from a wall in an empty room. what happens if anything to the amplitude and frequency of the waves on reflection?
Amplitude ---------------------------------
Frequency --------------------------------
(ii) why are the sound waves unlikeely to have been diffracted as well?
(c) Undern what circumstances could these sound waves be diffracted?

2007-05-14 03:50:44 · 1 answers · asked by riazshahid67 1

To be more specific, I have a 72V motor with 3HP power, 3000rpm at 40Amps current, which is bi-directional. Can it generate electricity when attached to a windmill or any kind of rotation source?

2007-05-14 03:33:41 · 5 answers · asked by Bhavin 1

2007-05-14 03:32:28 · 3 answers · asked by Anonymous

All I know is it has something to do with the gravity of moon. A explanation with mathematical model would be appreciated but not required. thank.

2007-05-14 03:17:40 · 1 answers · asked by ?ټ֠? size= 1

the joulemeter is measure the electrical energy supplied.when 7200j of electrical energy is supplied to heater the temperature of the 0.50kg block rises from 10 degree celious to 40 degree celious.
(a) calculate a value for the specific heat of capacity of iron.
(b) the actual value for the specific heat capacity of iron is 450j/(kgk) give a reason for the difference between these two values.
(c) state one way of improving the accuracy of the experiment.

2007-05-14 03:11:26 · 3 answers · asked by riazshahid67 1

2007-05-14 03:04:03 · 3 answers · asked by fz n 2

OK, here is my question: F = MA, so if I strike a golf ball and my club is not accelerating. Why does the ball move? If acceleration is exactly zero then shouldn't the force equal zero also? I know it would be hard in reality to swing a golf club with exactly zero acceleration, but I am more interested in the concept, not how it necessarily applies to golf. And how does negative acceleration work in this situation?

2007-05-14 03:01:35 · 8 answers · asked by Anonymous

Can anyone give me two examples of each? Please and thank you. :)

2007-05-14 02:58:25 · 3 answers · asked by Jenna - Adopt Me Angelina 3

What about a hi-powered assault weapon, similarly?

2007-05-14 02:01:46 · 12 answers · asked by john-evan 1

2007-05-14 01:50:23 · 11 answers · asked by Anonymous

Calculate the average mass density of the earth. The earth's mass is 5.98x10 to the power of24kg and it's radius is 0.38x10 to the power of 6 m.?

2007-05-14 00:11:08 · 6 answers · asked by ramil e 1

About 2/3 of your body mass consists of water. calculate the volume of water in a 80kg person.?

2007-05-14 00:07:08 · 5 answers · asked by ramil e 1