Physics - November 2006

2006-11-29 09:38:53 · 2 answers · asked by xenon1989 2

A uniform plank of length 5.3 m and weight 215 N rests horizontally on two supports, with 1.1 m of the plank hanging over the right support (see the drawing). To what distance x can a person who weighs 453 N walk on the overhanging part of the plank before it just begins to tip?

Here is the drawing
http://www.webassign.net/CJ/09_14.gif

2006-11-29 09:21:31 · 1 answers · asked by Hey Carl 1

Im doing a project and my ohms meter is really not working really well. I am testing zinc and copper under different temperatures. One at room, a cold temperature and a hot temperature. How should the conductivity of each metal be ranked under the different temperature. Can you make an apporoximate list. Also im using an ohmsmeter on 20k. If you can can you give me some conductivity measures it should approximatly be.

At this point i have nothing else i can do because this project is due tommorow. So please anything you got please tell.
Thanks

2006-11-29 09:17:59 · 1 answers · asked by Anonymous

I borrowed an ohmms meter from my school and im having trouble with it. When ever i bring the two probes to the metal I am testing which is copper the reading doesnt stop. It seems to be to sensitive and the reading just keeps changing and sometimes just goes to zero. Can you tell me a teqnique I can do or anything so i can get a reading. Thanks

2006-11-29 09:11:29 · 3 answers · asked by Anonymous

An electric heater draws 1100W of power. Electricity costs 8¢ per kW.h. How much does it cost to operate the heater 3h a day for 30 days.

I know the answer is $7.92

Since i need 1100W in to KW.h in order to solve, how would i approach from 1100W (or 1.1kW) to unit of kW.h

2006-11-29 09:07:26 · 6 answers · asked by Anonymous

Answer expressed in Newtons.

2006-11-29 08:51:04 · 2 answers · asked by theresa_xo92 2

I'm doing coursework on resistance and i've done all of the experiments and what not but i'm stuck on what to put on the introduction as we have to put some background information on resistance and how it works ect.
I've put a basic description of what resistance is and the formula for it but I need some more information.
Why does the Voltage divided by the current equal the resistance?
What does resistance effect in real life?
I need to know things like that.

2006-11-29 08:43:28 · 4 answers · asked by claireybearyfairy 4

I have an ohmsmeter that i borrowed from my school to measure resistance. I set it to 20 k. I want to know what unit the K stands for and how i should write the final measurement. Also i want to change resistance to conductivity. Do you know what the conversion factor is and can you give me an example. Say when set to 20k it measures .22. what will the conductivity be. Also right it with the appropriate units.

THanks very very much

2006-11-29 08:28:54 · 8 answers · asked by Anonymous

2006-11-29 08:28:05 · 6 answers · asked by whoknows 1

A 750W toaster and a 1200W electric frying pan are plugged into the same 100v outlet. How much will it cost to operate the two aplliances at 8¢ per kW.h?

My Work:

750W = 0.75kW
1200W = 1.2kW
0.75kW+1.2kW = 1.95kW
8¢/kW.h = $0.08/kw.h

Therefore: 1.95kW.h x $0.08/kW.h = $0.156

Am i right?
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My teacher told us that the answer is $1.56. So please help me.

PS: Where I have converted the 750 and 1200 W into kW (that is correct), but when i calculate the final cost i put 0.75kW.h and 1.2kW.h <<-- is adding the .h at the end like that allow?

2006-11-29 08:19:18 · 4 answers · asked by Anonymous

2006-11-29 08:13:06 · 4 answers · asked by Kylie 1

2006-11-29 08:11:52 · 6 answers · asked by Kylie 1

2006-11-29 08:10:54 · 6 answers · asked by freeminder 2

2006-11-29 07:49:38 · 6 answers · asked by Anonymous

were can I find out how polerized sun glasses work

2006-11-29 07:14:45 · 6 answers · asked by Anonymous

For example, if a survivor of a nuclear bombing came to your fallout shelter or basement with radioactive fallout all over him or her, and you thoroughly washed all of the dust off of him or her, won't his or her own exposure to the fallout have particles radiating out of his body?

If not, then what exactly is radiation sickness -- is it the inhaling or injesting of the dust?

I just don't see how the dust can radiate into our bodies, but human bodies cannot -- is it not the chemical reactions of raioactive material in contact with non-radioactive material that causes radiation?

And even if you kept your distance from him or her, wouldn't the radiation radiate from him, through the air, to you and everywhere else like a chain reaction?

2006-11-29 07:13:12 · 6 answers · asked by ? 3

how exactly?

2006-11-29 07:11:20 · 4 answers · asked by dudez 1

need to know why itz part of my coursework

2006-11-29 07:09:40 · 7 answers · asked by dudez 1

2006-11-29 07:06:10 · 12 answers · asked by nothingspecial 1

I need to know about heat conduction. Like, the different types of heat conduction. Nothing specific. Just some info would be nice :-).
Thanks!

2006-11-29 06:55:11 · 3 answers · asked by Jahzarra 2

The Space Shuttle on reentry, slows its velocity from 565km/hr to 496km/hr in 15 seconds, then in the next 17 seconds it slows to 346km/hr at touch down. What is its acceleration during this time frame.

2006-11-29 06:55:02 · 2 answers · asked by Anonymous

2006-11-29 06:52:03 · 2 answers · asked by Anonymous

If a cheetah accelerates from rest at 7.8m/s squared in order to reach 70 mph in a distance of 30 meters. How much time has elapsed?

2006-11-29 06:49:32 · 3 answers · asked by Anonymous

2006-11-29 06:43:56 · 5 answers · asked by ? 1

If a space ship was traveling at a near zero relative speed and suddenly accelerated to a great speed, wouldn't their inertia combined with the vessel's rapid acceleration turn them into quivering piles of jelly?
Star Trek has people going from impulse speed to 9 times the speed of light inside of a second! OK OK, they have some wonder device called inertial dampeners, but if they didn't... wouldn't they all become instant stains on the backs of their chairs???
Put simply, can you have 'G-Force' via acceleration in zero gravity?

I believe Albert Einstein said gravity is a form of acceleration, but not sure if/ how that applies due to lack of formal education.... PLEASE HELP!

2006-11-29 06:31:33 · 4 answers · asked by stillwaitingtobeimpressed 2

Of course I know that a seat belt and all that would prevent further harm to the driver / passenger. I'm curious about the complete physics of a car crash.

2006-11-29 06:19:58 · 2 answers · asked by Sir Guitarist 2

yah.. i need an answer that connects wid physocs.. anyone have any ideas??

2006-11-29 06:07:14 · 9 answers · asked by dudez 1

i have a paper which is:measuring the specific heat of a solid body.the problem is that i can't find any information to add to my paper which is only 3 pages.plz any infos or where to look?

2006-11-29 05:43:37 · 2 answers · asked by alex355 2

the equation to find the center of mass of a rigid object by giving examples.

2006-11-29 05:42:12 · 3 answers · asked by peter 1

If so, the frequencies consist of electrons (mass) jumping from atom to atom -- right? So how can mass pass through our bodies seemingly harmlessly? I've noticed that the higher frequencies tend to be the ones that do harm us. What is it about the speed of a wave that damages our bodies? Is it the frictional heat of the atoms having to slow down so quickly when they reach our "denser than air" bodies?

2006-11-29 05:41:10 · 2 answers · asked by ? 3