Physics - December 2007

It's Vout/ Vin or something, but i'm not completely sure... Help!

2007-12-18 05:31:58 · 1 answers · asked by sambrown2k6 1

2007-12-18 05:28:24 · 8 answers · asked by Anonymous

a box of books weighing 325 N moves at a constant velocity across the floor when the box is pushed with a force of 425 N exerted downward at an angle of 35.2 degrees below the horizontal. Find ,uk between the box and the floor...?

2007-12-18 05:22:30 · 2 answers · asked by Anonymous

a box of books weighing 325 N moves at a constant velocity across the floor when the box is pushed with a force of 425 N exerted downward at an angle of 35.2 degrees below the horizontal. Find ,uk between the box and the floor...?

2007-12-18 05:18:50 · 2 answers · asked by Anonymous

have UV lights that I would like to put in a tube and block it's harmful UV rays. I plan to use a polycarbonate tube, but I'm getting conflicting answers on wikipedia if it 100% blocks harmful UV.

http://en.wikipedia.org/wiki/polyca...
Above link it says polycarb resists UV fairly. (right and colum in yellow)
On the same page bellow the graph it says: 0% transmission at almost exactly 400 nm, blocking all UV light transmission."

Then here:
http://en.wikipedia.org/wiki/uv_lig...

It says under "Eye" paragraph. "Some plastic lens materials, such as polycarbonate, inherently block most UV."

What's the straight story on this?

2007-12-18 05:11:26 · 9 answers · asked by honeyroastedeggroll 1

One more quition when the world goes around , are we upside down where gravity holds us down.

2007-12-18 04:34:09 · 8 answers · asked by Anonymous

a 75 kg box slides down a 25.0 degree ramp with an acceleration of 3.60 m/s^2. Find ,uk between the box and the ramp. What acceleration would a 175kg box have on this ramp?

2007-12-18 04:21:42 · 3 answers · asked by Anonymous

A student pulls on a rope attached to a box of books and moves the box down the hall. The studen pulls with a force of 185 N at an angle of 25.0 degrees above the horizontal. The box has a mass of 35.0 kg, and ,uk between the box and the floor is 0.27. Find the acceleration of the box.

2007-12-18 04:10:10 · 5 answers · asked by Anonymous

How do you think that energy was created? I know that most people will say that God or another diety created it, but I want to hear the scientif reasons such as the gravitational energy being a negative charge and cancelling out, etc. Please post your answers!

2007-12-18 04:04:16 · 19 answers · asked by Emily loves Nirvana 2

A 25 kg chair initally at rest on a horizontal floor requires a 165 N horizontal force to set it in motion. Once the chair is in motion, a 127 N horizontal force keeps it moving at a constant velocity. (a) Find the coefficient of static friction between the chair and the floor. (b) Find the coefficient of kinetic friction between the chair and the floor.

2007-12-18 03:43:13 · 2 answers · asked by Anonymous

i have to make a working model on the uses of static electricity. i have successfully able to geerate enough from the van de graff generator i had made. now i have to use that electricity in some working model to show some uses. any ideas?

this is a part of my physics project.

2007-12-18 03:42:48 · 2 answers · asked by Arnab Roy 3

What's the world's fastest speed a human can achieve by RUNNING. if you give me by m/s or mi/hr would be appreciated.

thanks

2007-12-18 03:26:35 · 4 answers · asked by Heavy-Metal123 3

In layman's terms, why is it that Einstein's famous equation showing that matter is just concentrated energy (E=mc2) and matter-energy can be converted into eachother, why is it that it so happens to be the speed-of-light squared (times mass) that is equal to energy??? What is so special about the speed of light, which is just how fast light photons move?

Why isn't it 122,000 miles per second squared x mass = energy or 1,000,0000 miles per second squared x mass = energy???

What, exactly, is so darn special about the speedlimit of photon particles that somehow fits into an perfect equation relating to energy/mass equivalence? Is this just a miraculous, unbeliavable coincidence that the number just so happens to be the speed of light that is squared?

Thanks! I look forward to reading your responses!

2007-12-18 03:21:46 · 8 answers · asked by Anonymous

Persons that catch on fire while sleeping. THat they just start burning with no reason. And in the show they gave actual cases in the U.S and England. Does anyone know if its true? ANd if it is what is it call and how does it happen??

2007-12-18 03:16:45 · 5 answers · asked by Anonymous

I am having some trouble getting my matrix math correct. I have a translation, rotation, and scale matrix working properly, but I want the rotation to be about an arbitrary axis. I have found a formula for a 3D matrix, but i only have x,y,w. Any help would be greatly appreciated and needed

2007-12-18 03:02:03 · 2 answers · asked by G M 2

I somehow managed to magnetize my screwdriver and i have no idea how i did it. Any help would be wonderful

2007-12-18 02:23:38 · 0 answers · asked by Anonymous

a battery is connected in series with a 2 ohms resistor and a switch. a voltmeter connected across the battery reads 12 V when the switch is open but 8 when it is closed. what is the internal resistance of the battery?

2007-12-18 02:05:36 · 3 answers · asked by blahhs 1

2007-12-18 01:52:50 · 16 answers · asked by Lord of Chaos 4

2007-12-18 01:43:47 · 8 answers · asked by Anonymous

complete physic explanation please...

2007-12-18 01:29:39 · 3 answers · asked by Anonymous

I know this is stupid but how come a battery cannot light gor example a household bulb?

And another question. What does a higher current do to a bulb and what does a higher voltage do to a bulb e.g brightness?

What type of bulb would a 6V battery light?

Thanks. Electricity bugs me.

2007-12-18 00:25:43 · 8 answers · asked by alanjb 1

Why is a thicker conductor necessary to carry a current in A.C.as compared to D.C.

2007-12-17 23:58:43 · 2 answers · asked by deepak 1

2007-12-17 23:56:27 · 1 answers · asked by Anonymous

2007-12-17 23:29:14 · 7 answers · asked by Anonymous

2007-12-17 23:23:19 · 9 answers · asked by Anonymous

how to translate the 3D objects on the sdreen by using c++ code?

2007-12-17 23:22:39 · 1 answers · asked by emebet y 1

2007-12-17 22:44:43 · 4 answers · asked by Joshua 2

a) -4D
b) -1/4D
c) -2D
d) -I/2D

2007-12-17 22:02:35 · 8 answers · asked by ♥aesu♥ 1

2007-12-17 19:04:51 · 2 answers · asked by girish k 1

A proton is accelerated from rest through a potential difference of 25700 V

a) whats the kinetic energy of this proton in joules after this acceleration?

b) whats the speed of the proton after this acceleration?
------------
ok once u find the E.P.E , which is E.P.E = V * q
but then what? AND WHY? IF Electrical Potential Energy= Kinetic Energy in this case , PLEASE EXPLAIN WHY.

2007-12-17 18:31:01 · 7 answers · asked by G3P 3