Physics - May 2007

in a related topic to the diamond questions earlier, what does it mean to say the hardest material in the world... if you place it on a steel floor and smash at it with a sledge hammer it wont break? i know from mild common sense that that is rubbish, but could someone give me an examplpe such as that to demonstrate the unbeatable hardness of Aggregated diamond nanorods or anything!?

2007-05-30 13:07:36 · 6 answers · asked by Anonymous

A submarine changes depth by altering its
a. speed
b. density
c. total area
d. shape
A:b

2007-05-30 12:58:11 · 7 answers · asked by Ryoma Echizen 3

2007-05-30 12:39:05 · 4 answers · asked by super_cat53 1

2007-05-30 12:30:09 · 2 answers · asked by Anonymous

Natural gas is transported through pipeline at pressure
P = 100 atm = 1e7 Pa.

What is the tension in the walls of the pipe?
(Note: tension (i.e. stress) could be anisotropic).

2007-05-30 11:06:06 · 1 answers · asked by Alexander 6

From
http://apcentral.collegeboard.com/apc/public/repository/ap07_physb_frq_kw.pdf
I took the AP Physics B test and was unsure of my answers to question #3, as circuits in general have always been my weak point, although many thrive when learning such a concept. I would truly appreciate it if someone could provide assistance by detailing the generic procedure that should have been followed. I always balk when no specific values are given for each variable.

2007-05-30 10:49:49 · 2 answers · asked by Nickz 1

As usually, I would prefer to see a formula.

2007-05-30 10:35:17 · 6 answers · asked by Alexander 6

It has something to do with air pressure, but i'm not entirely sure. Help!

2007-05-30 10:25:10 · 7 answers · asked by Jennifer S 1

assume i'm in space and staying motionless, is it possible to get myself moving just by swinging my arm forward really hard? because i'm sitting on my bed right now and try to do so and it seems my body does go back alittle.

2007-05-30 10:08:56 · 5 answers · asked by      7

A man is in a boat out away from shore. The mass of the man, the boat and everything in it is 215 kg. The boat is not moving. The man throws and anchor with a mass of 19 kg straight out from the boat with a speed of 15 m/s. What is the resulting speed of the boat?

2007-05-30 09:57:48 · 3 answers · asked by Anonymous

I need to buy 5kv inverter.the shops are quoting in watts.Thanks for your anticipated answer[s]

2007-05-30 09:48:59 · 5 answers · asked by G.xi 1

According to some people, they are unable to wear analogue watches because they cause them to run backwards, and also cause digital watches to function strangely. Can this be true?

2007-05-30 09:38:39 · 10 answers · asked by circltriangl 1

2007-05-30 09:25:31 · 1 answers · asked by goring 6

2007-05-30 09:09:12 · 11 answers · asked by Phillip 3

A rotating door is made from four rectangular glass panes, as shown in the drawing. The mass of each pane is 93 kg. A person pushes on the outer edge of one pane with a force of F = 60 N that is directed perpendicular to the pane. Determine the magnitude of the door's angular acceleration.
_______rad/s2


http://www.webassign.net/CJ/09_34.gif

2007-05-30 09:02:18 · 1 answers · asked by Anonymous

2007-05-30 08:01:46 · 3 answers · asked by ? 5

Jack and Jill are standing on a crate at rest on the frictionless, horizontal surface of a frozen pond. Jack has a mass of 75.7 kg, Jill has a mass of 45.5 kg, and the crate has a mass of 15.7 kg. They remember that they must fetch a pail of water, so each jumps horizontally from the top of the crate. Just after each jumps, that person is moving away from the crate with a speed of 4.10 m/s relative to the crate.

What is the final speed of the crate if both Jack and Jill jump simultaneously and in the same direction? (Hint: Use an inertial coordinate system attached to the ground.)

What is the final speed of the crate if Jack jumps first and then a few seconds later Jill jumps in the same direction?

What is the final speed of the crate if Jill jumps first and then Jack, again in the same direction?

(all solutions are in m/s)

2007-05-30 08:00:17 · 3 answers · asked by Anonymous

I know that pressure increases if you increase temperature and why, but why does it occur the other way around? Thanks!

2007-05-30 07:29:38 · 10 answers · asked by Anonymous

If a hole was drilled trough the center of the earth, and it would be completely clear(no liquid hot magma),if you jumped through it would you gain speed until you got to the center, slow down and then fall back the other way, eventually floating in the exact middle of the earth.

2007-05-30 06:20:08 · 6 answers · asked by Anonymous

what is the reason copper conducts electron?

2007-05-30 06:19:39 · 3 answers · asked by din e 1

If there was dust cloud around solar system, and we could
not see the stars, how would we explain planetary motion?
The planets would have mystical certrifugal forces acting
on them, which have no source.

2007-05-30 06:19:38 · 2 answers · asked by Alexander 6

I'm particularly interested in the ability for one to shift to the other and the potential for superimposition...

2007-05-30 06:13:33 · 3 answers · asked by Anonymous

why does it rotate ..


and what direction?

2007-05-30 06:10:28 · 6 answers · asked by Anonymous

The same gravity that pulls the surface of the earth in also pulls out at a certian point [gravitational equalibrium]. centrifugal force causes thicker section on the equator thus thinner on the poles other wise you would weigh many times more on the poles.

2007-05-30 05:56:34 · 9 answers · asked by james h 2

Okay. So imagine someone is sitting in a car and they have a dog on their lap. They are driving up to a weigh station to be weighed. Right at the exact moment that the weight reader person takes the reading, the driver throws the dog up into the air. (so the weight measurement is taken when the dog is in mid-air) SO, would the truck weigh the same or less than if the driver just kept the dog on his lap?

Its got me befuddled because isnt there a law of physics about how energy is neither created nor destroyed? So my thought was that the weight of the dog would be transferred to the driver as he tosses him up in the air. (the dogs weight force goes DOWN when he goes UP) But then part of me thinks that maybe if the dog is mid-air right when the weight measurement is taken, the weight has temporarily been suspended.

Argh... its driving me crazy! What would the correct answer be?

2007-05-30 05:56:08 · 7 answers · asked by Anonymous

from what I understand of E=MC2, as velocity goes up so does mass, and if you are going light speed your mass is infinite. how does that not break the law of conservation of mass

2007-05-30 04:20:20 · 13 answers · asked by outbaksean 4

2007-05-30 04:18:59 · 13 answers · asked by Anonymous

I believe in UFOs, and I've always wondered why they don't break the sound barrier when obviously they are going more than Mach 1? I think they are displacing space, rather than canceling mass.

2007-05-30 04:04:07 · 4 answers · asked by Ken 1

with the height of the people in the geographic location where gravity is stronger & weaker. Before the advent of world travel.



http://news.bbc.co.uk/2/shared/spl/hi/pop_ups/03/sci_nat_enl_1059064160/html/1.stm

2007-05-30 03:11:29 · 4 answers · asked by bear5521 2

It is hard for me to believe it but I survive but never want to try for the third times. I simply disappeared and reappeared.

2007-05-30 01:29:13 · 15 answers · asked by Anonymous