Physics - May 2007

that are unchanged when reflected in a horizontal line?

2007-05-15 18:24:10 · 6 answers · asked by ✶ 4

i need a scientific explanation. easy to understand please. =)

2007-05-15 16:44:23 · 13 answers · asked by Anonymous

2007-05-15 16:34:19 · 8 answers · asked by Gromac 3

2007-05-15 16:13:31 · 2 answers · asked by mark 1

2007-05-15 15:34:32 · 5 answers · asked by Kaji707 2

Given the substance, it's density, volume, mass, and weight, how do you calculate the apparent weight and Bouyant force, assuming the substance is totally submerged in water?

Example:
Substance - Steel
Density - 7.8 g/cm^3
Volume - 1 m^3
Mass - 7.8 kg
Weight - 76.44 N

2007-05-15 15:15:44 · 2 answers · asked by lizard01007 3

2007-05-15 15:12:38 · 4 answers · asked by Elizabeth L 1

I like my cats, I would never do that to them.

2007-05-15 14:59:16 · 5 answers · asked by eggman 7

its says find a date in your town or abroad, browse the profiles and join for free........well i'm getiing more than 50 hook ups within a week ! hmmm..now here's the million question
are these so called "frenz from aboard" for real n do they really exists?

2007-05-15 14:44:40 · 1 answers · asked by jooki d 1

2007-05-15 13:41:11 · 7 answers · asked by Anonymous

2007-05-15 13:34:39 · 5 answers · asked by Antonio G 1

Motion does not effect weight. But why not?

2007-05-15 12:57:02 · 8 answers · asked by Anonymous

I have heard it said before that unlike every other scientific theory; in which if some evidence or a result arises which contradicts the theory, a new theory then has to be hypothesised and the old one 'thrown out'...

...the Big Bang theory is the only one in which as tests and results have come back to the lab, the theory has just been adapted to make it work. (I.e. dark matter being introduced to make the maths work).

Is this an accurate statement?

I personally don't doubt the idea of the Big Bang, it just seemed curious scientific practice if this were true.

P.S: Ironically enough, I read on the BBC science news website that hubble had just taken a picture which apparently 'showed dark matter' for the first time. (Clearly a method behind the madness)

2007-05-15 12:35:32 · 4 answers · asked by Adam L 5

This is silly that I have to repost this question, because Y!A has deleted my previous one. If at noon, a starship travelling at speed (1/2)c, sees a reflection of its own clock in a stationary mirror showing 11:00 am, what time will it be when the starship strikes the mirror?

2007-05-15 12:07:06 · 2 answers · asked by Scythian1950 7

How does an electron have the same charge?? It's so small compared to a proton!! makes no sense to me.. :( Someone with knowledge please explain!!

2007-05-15 12:01:24 · 2 answers · asked by Kathy C 1

Once again, look at Alexander's question and the follow up question:

http://answers.yahoo.com/question/index;_ylt=ArVMRKyqf5weyNEklQHMoXDsy6IX?qid=20070515120146AA2qnnG

Now, we have twins A and B, both with wristwatches, set at noon at the time twin B departs. Twin A remains stationary. Twin B travels at speed (1/2)c for 1 hour, and returns at speed (1/2)c for 1 hour, per twin A's watch, so that A's watch now shows 2 pm. Both A and B have telescopes trained on each other's wristwatches. What is the function of times B(Ta) and A(Tb), where B is B's time as seen by A in A's time Ta, and A is A's time as seen by B in B's time Tb?

I wish the answer to this would be explained more often to those totally puzzled by the Twin Paradox. Are functions B(Ta) and A(Tb) symmetrical?

2007-05-15 11:51:15 · 2 answers · asked by Scythian1950 7

A hard drive for example:
all the data moves faster on the first partition.
as you move closer to the center of the hard drive data moves slower.

if so, couldn't faster linear velocity also explain the debate over the age of the universe.
if space time are not constant then age also becomes moving as well.
just wondering what your thoughts are.

2007-05-15 11:00:47 · 4 answers · asked by Anonymous

and does it have anything to do with string theory?

2007-05-15 10:33:25 · 6 answers · asked by SHELLTOE BISCUITS 3

My bf and I were discussing acceleration. I say that the sign of it depends on your frame of reference, and that it's okay to have it be negative. For example, gravity is generally considered to be negative. He thinks, however, that, since acceleration is a vector, it's always positive. Can you help rectify this? I'm sure there's some way that we're both right. . .
Thanks!

2007-05-15 10:05:27 · 12 answers · asked by Sci Fi Insomniac 6

A. 2,940 J
B. 5,880 J
C. 6,000 J
D.12,000 J


A car with a mass of 1,200 kilograms is moving around a circular curve at a uniform velocity of 20 meters per second. The centripetal force of the car is 6,000 newtons. What is the radius of the curve?

A.160 meters
B.80 meters
C.32 meters
D.16 meters

2007-05-15 09:16:04 · 1 answers · asked by Anonymous

2007-05-15 08:46:23 · 6 answers · asked by livefast_dieyoung 2

2007-05-15 08:46:03 · 4 answers · asked by CHARLES P 1

i am really confused with the two,,
ok in a potentiometer does the current always stay the same while we can vary the voltage,,

and dont they both do the same thing,, i mean you can reduce the resistance in a rheostat in series and hence get a greater voltage across the component,, isnt this the same thing as a potentiometer,,!!!
well we connect the potentiometer in parallel to get a specific voltage right,, so why to we regard them as two totally different things!!

by the way i have my A/l level physics practical test tommorrow,, so help is much appriciated

i am totally confused with the two can someone explain clearly what i need to know,,,

thanks alot!!!

2007-05-15 08:16:58 · 8 answers · asked by torpedo 1

The height from which you are released is 62.5 meters. However, the last 20.8 meters are used to slow you down from your maximum speed to rest (it's a good thing). Based on these two heights, what would be the following, taking the ground to be the origin, and up to be the positive direction:

(i) The change in position from the release point to the point at which the braking mechanism engages is -41.7 meters up.

How do you calculate the time you are in free fall (the time it takes you to travel from the release point to the point at which the braking mechanism engages?

2007-05-15 08:08:25 · 4 answers · asked by Anonymous

1) Explain in molecular terms, why considerable heat energy is needed to convert 1g of water into 1g of steam at 100°C, without any temperature change taking place.

2) In an experiment, 120g of ice at 0°C is to be melted. the specific latent heat is of ice is 340J/g. Assume all the energy from the heater is going to be used to melt the ice.

Calculate the expected time for which the 60W heater is switched on.

(please explain answers!!)

2007-05-15 07:57:39 · 3 answers · asked by virtualgirlsweetheart 2

2007-05-15 07:54:25 · 4 answers · asked by karl k 6

If I place a 6 V, 0.06 A filament lamp in a circuit and I want to measure the voltage across the filament lamp and the current in the circuit, what would be a suitable range settings for the multimeter and why?

Thanks for your help.

2007-05-15 07:45:06 · 3 answers · asked by Anonymous

please help!

2007-05-15 07:31:34 · 3 answers · asked by maria 2

2007-05-15 07:30:22 · 3 answers · asked by Anonymous

what is the shortest distance in which the elevator can be brought to its top with its decending with a speed of 4ft/sec square?

2007-05-15 07:21:26 · 4 answers · asked by Alvin A 1