Physics - April 2007

How many conduction electrons are there in a 5.00 mm diameter gold wire that is 30.0 cm long?

using golds electron density as 5.9 * 10^28 I got 3.48*10^23

but now

How far must the sea of electrons in the wire move to deliver -21.0 nC of charge to an electrode?

and Im stuck... again >.>!
Thanks for the help guys :)

2007-04-04 09:52:36 · 2 answers · asked by Dobie 2

The space shuttle contains a chair. If you kicked the chair, would you still stub your toe?

2007-04-04 09:09:48 · 5 answers · asked by Anonymous

2007-04-04 09:08:47 · 4 answers · asked by KhanS 2

If the universe is expanding, then everything in the universe is in motion. Some things are moving faster than others. If time is relative to your frame of reference, and everything is moving at different speeds, then time passes differently for each of these different things. What sense, then, does it make to ask how old the universe is or how long ago the big bang happened? Would you get different answers depending on where you were in the universe? For the faster moving objects, the universe must be younger than it is for the slower moving objects. Or am I missing something?

2007-04-04 09:07:37 · 5 answers · asked by Jonathan 7

2007-04-04 09:03:01 · 3 answers · asked by Jordan 1

2007-04-04 08:54:47 · 5 answers · asked by Sathits 1

do the terms wave speed and wave frequency refer to the same thing?

2007-04-04 08:34:57 · 5 answers · asked by JJ99 1

2007-04-04 08:28:16 · 2 answers · asked by carspare 2

2007-04-04 08:27:07 · 9 answers · asked by Anonymous

We had an argument in class today, my science book says it is not proven to be either and that there are theories on what it is.

2007-04-04 08:22:26 · 11 answers · asked by Anonymous

2007-04-04 08:08:09 · 8 answers · asked by Jordan 1

lamp fitting above the shower. I took the lamp out when we moved in thinking the UV is dangerous to humans.

2007-04-04 07:47:41 · 6 answers · asked by turtle 1

"why is a vibrating guitar string not as loud when it is mounted to a workbench as it is when it is mounted to a guitar?"

2007-04-04 07:28:59 · 3 answers · asked by JJ99 1

the toy. When the teacher removes her hand, the toy pops straight up and just brushes against the ceiling. She does this demonstration five times, always with the same result.

When the teacher repeates the demonstration for the sixth time the toy crashes against the ceiling with considerable force. The students notice that in this trial, the spring and toy sperated from the base at the moment the spring released.

The teacher puts the toy back together, repeats the demonstration and the toy once again just brushes against the ceiling.

Explain in terms of mass and energy, why the spring toy hits the ceiling in the 6th trial and not in the other trials.

2007-04-04 07:27:27 · 2 answers · asked by Anonymous

2007-04-04 07:20:05 · 4 answers · asked by Jordan 1

Would you start it on mt. Everest?

2007-04-04 07:19:52 · 6 answers · asked by Anonymous

Is there a device that can detect all the radio wave transmissions or general electromagnetic waves around me (you know from radio towers, cell phones/towers, etc), even the faint signals and can tell me their signal strength in watts?

Tx

2007-04-04 06:35:42 · 3 answers · asked by zerohourx 1

Can anyone tell me what physics laws apply to an xylophone? Also, just a guitar string being played?

2007-04-04 05:42:33 · 3 answers · asked by sportfreak490 2

Rotating object consists of two solid spheres with a radius of 0.2 m and a mass of 2
kg each. They are connected by a thin rod, which is 0.8 m long. Calculate moment of
inertia about the axis going through the center of one of the spheres

2007-04-04 05:29:32 · 3 answers · asked by ? 1

For about two months now, everytime someone flushes the toilet it tries to flush clockwise. If you don't push the lever and poor water, from a bucket, in the bowl it will flush clockwise. I need to know how this is possible and why it is doing this.

2007-04-04 05:15:17 · 4 answers · asked by Sarah R 1

Many thanks for answering.

2007-04-04 05:14:19 · 3 answers · asked by Dovey 7

Not homework. Just for me. Thanks.

2007-04-04 05:12:48 · 7 answers · asked by Dovey 7

Hi, could someone walk me through rearranging the equation s=ut+1/2at^2 for a and for t. I'm pretty sure i've been able to rearrange it for a; a = sqrt (s/t), but the t variable i'm struggling with owing due to the fact that the equation has 2 t's in it. Any help would be appreciated, thanks.

2007-04-04 04:31:36 · 2 answers · asked by David M 1

Assuming a constant value of 1.29 kg/m3 for the density of air, determine the height of the building.

2007-04-04 04:02:59 · 1 answers · asked by Fuzz 1

2007-04-04 04:02:57 · 6 answers · asked by mathorator.. 1

Please solve, thx!
A 1 kg flag is attached to a uniform horizontal flagpole (mass=5kg) where the flag hangs vertically. The pole is 5 meters long and the flag is attached at two points, namely the end and 1 meter from the end. What is the torque produced by the flagpole-flag combination where the pole is attached to the wall?

2007-04-04 03:57:27 · 1 answers · asked by GSU 1

Please solve, Thank You!
A uniform circular disk with mass (20kg and radius = 5cm) rolls (without slipping) down a hill with a vertical drop of 2 meters, what is the disk’s angular velocity (rads/sec) at the bottom of the hill. Find the moment of inertia

2007-04-04 03:56:10 · 2 answers · asked by GSU 1

A 5.0 kg ball is moving at 4.0 m/s to the right and a 10 kg ball is moving at -2.0 m/s to the left. The total momentum of the system is??

a) 0.0 to the right
b) 20 kg m/s to the left
c) -20 to the right
d) 40 to the left
e) 17 to the right

please help/explain thanks

2007-04-04 03:53:04 · 4 answers · asked by Anonymous

2007-04-04 03:52:36 · 4 answers · asked by dondre d 1

A 4.0 kg ball is traveling at 10 m/s and strikes a wall. The 4.0 kg ball bounces off the wall wih a velocuty of -9.8 m/s. The change in momentum of the ball is??

a) -79.2
b) 130
c) -260
d) 24
e) -56

please help/explain thanks

2007-04-04 03:50:57 · 4 answers · asked by Anonymous