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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
41,724 
I heard somewhere that friction on an inclined plane is independent of the mass of the object. However on youtube, it...

Mar212 12:56 AM
Jandaberg123

2 
734 
Would a big ball weighing 100kg with a diameter of 1 meter float in water?
I guess my question is, no matter how...

Mar112 06:07 PM
Redbelly98

4 
840 
I have a problem with the determination of the correct focal curve of an achromatic double.
I'm considering here a...

Mar112 05:13 PM
Andy Resnick

6 
1,392 
The question really explains the primary question but I have another quick one as well.
How come sound isn't...

Mar112 03:10 PM
Naty1

1 
928 
Hey all,
I'm a complete layman at all things magnetic, and lately I've been trying to understand how the earth's...

Mar112 03:04 PM
cephron

0 
1,102 
Hi
I have a question on AOMs used in a double pass configuration. I understand the motivation for such a setup, but...

Mar112 02:30 PM
Niles

2 
710 
Hi,
I am interested in trying to better understand the nature of fields in terms of a possibly somewhat contrived...

Mar112 09:50 AM
mysearch

5 
1,649 
In all the electric motors I have taken apart, the coils on the armature have never been insulated. This has always...

Mar112 07:35 AM
Delta Kilo

12 
1,222 
When I throw a ball up in the air, my acceleration will still be 10m/s^2 right? Just that my original upwards force...

Mar112 06:29 AM
Michael C

2 
954 
In a try to test my knowledge of Newton's laws, I have posed the following question to myself.
My attempt:
...

Mar112 05:26 AM
jaja1990

2 
635 
\frac{xx}{xx}=\frac{\sum s^{K}1}{\sum s^K} ...

Mar112 05:23 AM
RAfAEL_SP

2 
872 
This is not a homework problem, but a math question of curiosity. At 57 I am way past courses and homework.
If a...

Mar112 03:45 AM
vanhees71

2 
1,280 
Determine the speed of the elevator if each
motor draws in the cable with a constant speed of 5 m>s.
Here is a...

Feb2912 06:15 PM
Ken G

4 
2,343 
I've been playing around with projected capacitive touchscreens  specifically, the iPhone's. I've attached a white...

Feb2912 04:34 PM
pin0ut

2 
1,098 
Hi
Much of what I am going to write in this post is based on what I have read and understood (with very, very...

Feb2912 12:46 PM
berkeman

9 
1,117 
i wonder how we can describe the degree of diffraction of waves in a single slit in a mathematical formula , with the...

Feb2912 12:43 PM
technician

2 
1,189 
Is it true that Ampere's Law with Maxwell's correction is equivelant to BiotSavart Law?
Under what assumptions?

Feb2912 12:24 PM
Question Man

2 
1,882 
Is it true that in the case that light undergoes "total internal reflection" at a boundary, the transmittance T is 0,...

Feb2912 12:19 PM
Question Man

0 
843 
I am working on an engineering project in which I am mounting an electromagnet onto a small RC robot. The link for the...

Feb2912 10:56 AM
Hassan2

1 
1,608 
I found something interesting in the law of conservation of mechanical energy related with rotational kinetic energy....

Feb2912 10:31 AM
Hassan2

7 
1,539 
A Galilean transformation consists of a rotation (in space), a boost (in space) and a translation (in space and time)....

Feb2912 10:00 AM
Wox

1 
973 
For fluid with viscosity \mu our stress strain relationship takes the form
\sigma_{ij} = p \delta_{ij} + 2 \mu...

Feb2912 09:28 AM
Hassan2

2 
2,095 
IS gibbs free energy a useful idea to determine if a reaction will proceed or not?
Even if gibbs free energy is...

Feb2912 08:49 AM
jd12345

0 
687 
(I'm not sure if this would be a 'schooltype' question... it's definitively not for any kind of homework, so I'm...

Feb2912 07:36 AM
xpell

0 
745 
I dont really understand the concept of what makes work positive or negative for example if 3 charges are brought...

Feb2912 05:20 AM
tinytim

1 
957 
I want to build a plywood fish tank 16' long x 4' wide x 3.5' high. I need to know how to calculate the lateral force...

Feb2912 04:25 AM
jimhebert

17 
5,973 
Hi,
There are probably hundreds of books explaining (mathematically!!) how a directional coupler works....

Feb2912 03:16 AM
kaps_nit

0 
890 
Hey guys,
I was hoping somebody might help me; I'm really confused. I obtained the formula for distance, which is...

Feb2812 10:06 PM
delve

2 
804 
Hi all,
I hope that I'm posting in the right section of the forum. If not, I kindly request a moderator to move the...

Feb2812 06:39 PM
BaCaRoZzo

0 
833 
This likely represents a physical impossibility or contradiction, but I'd like to know that or, if not, understand...

Feb2812 06:30 PM
DrewD

6 
956 
I have a question about the ideal equilibrium MHD equation:
\vec{J} \times \vec{B} = \nabla p
where \vec{J}...

Feb2812 05:17 PM
vibe3

0 
1,117 
I know this is more of a chemistry question but it's come to this I'm afraid.
When calculating entropy changes in...

Feb2812 03:28 PM
tomothy

0 
1,295 
Hello,
I am trying to measure a couple of things related to thermal data. Is there a way to measure a transient...

Feb2812 02:06 PM
ProgrammerUK

0 
945 
Hi  am looking for some data points on how much suction is required to lift an object at different weights and...

Feb2812 11:30 AM
DaveC426913

1 
746 
I have a system that looks like this:
http://i.imgur.com/zKjqb.jpg
The top part is a piston, whereas the bottom...

Feb2812 08:58 AM
Kalus

0 
713 
As I was sitting at work the other day productively watching an aeroplane fly across the window I started to think of...

Feb2812 07:49 AM
Hassan2

5 
677 
I attached a file that shows the free EM action integral and how it can be rewritten. I would like to know how to go...

Feb2812 05:46 AM
Lapidus

1 
1,073 
Hi Guys,
Is there an easy way to determine this?
Say I have a 300mm Dia Pipe that @ 200deg C, ambient temp 30gec...

Feb2812 05:20 AM
xXx

6 
1,128 
I'm a little bothered with the inconsistency in notation of electric potential (V) and potential difference (ΔV)...

Feb2812 03:09 AM
Philip Wood

2 
1,242 
Few years ago, we have known about the phenomenon that Coca cola is overflow severely when a piece of Menthos candy is...

Feb2812 03:02 AM
NascentOxygen

3 
978 