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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
47,828 
say you have a very very long (or infinite) straight wire the carried a charge (glued to the wire) and the wire moves...

Aug612 03:28 PM
bigerst

4 
972 
D=Drag Coefficient
p=Density of air
A=Cross sectional area
v=velocity
a=acceleration
F= force
F air=(DpAv^2)/2...

Oct710 07:48 AM
tinytim

1 
1,553 
I have read that air pressure is about 100,000 pascalls
which = 100,000 newtons/m2
which is enough to accelarate a...

Sep1705 05:04 PM
Astronuc

5 
6,015 
I'm a little confused about "voltage". We learned that voltage is somewhat similar to electric field: a way to refer...

Nov1108 12:32 AM
jtbell

7 
1,843 
Good day,
I happened across an interesting interactive JAVA applet demonstrating the diffraction of light through a...

Apr1806 06:48 AM
BigMonkey

3 
1,839 
This is a concept that has always eluded me. I'm a Biologist who works in the Pharmaceutical Industry and I need to...

Aug2107 03:02 AM
Imagelist

15 
3,594 
hello everyone. Can anyone please help with following questions?
1. Can coefficient of friction (both static and...

Nov313 01:30 PM
clem

1 
433 
Hello all,
I officiate high school and college basketball. One of our rules concerning a dribble states...

Oct3007 02:09 PM
berkeman

3 
1,133 
These problems are really giving me fits, I would really appreciate some help.
A 12200 kg sailboat experiences an...

Sep2204 01:11 AM
Simonnava

5 
4,036 
Hello All....
I am just wondering about something.
The lift equation is,
L= \frac {C_L \rho A V^2} 2
...

Oct2407 04:31 AM
white flock

4 
12,417 
Hi, in class we were talking about lenses and how there is a certain focal length where all images 'far enough' away...

Mar1911 03:53 PM
Andy Resnick

1 
1,001 
Dear friends, and science lovers,
I am doing some statics problems with moment( crossproduct).And I've been...

Nov1613 01:51 PM
jhae2.718

1 
632 
Someones like teachers in my country says energy is vector and scalar .
Is that true ?
Anyone can prov that ?

Oct2312 08:02 AM
Studiot

7 
11,270 
Hello all .
Why mater victory to anti/matter after big bang ?
There is any relation to gravity ?

Nov2812 04:16 AM
Drakkith

2 
500 
Hello all .
I have two questions
Energy can create force ? for apply a force we need energy ?
Think about one...

Mar1213 09:40 PM
DaleSpam

20 
1,603 
Hi there,
I have noticed that when the wadding pool I work at is draining, a small whirlpool appears over the drain...

Jul1211 10:20 AM
chrisbaird

1 
1,396 
Hi all,
I am wandering if I can apply the KramersKronig (KK) relations to the complex wavenumber k(ω) = k'(ω) + i...

Feb1014 02:52 PM
maajdl

1 
276 
I need to calculate the the load F (in multiples of W) required to keep the link ABC in equilibrium under the action...

Sep2710 11:43 PM
bijesh_msg

0 
894 
From theory, we know that Boltzmann entropy for a given distribution, defined through a set of occupancy numbers {ni},...

Dec2112 09:08 AM
Rap

1 
817 
I was reading in my geology book (Earth: An Introduction To Physical Geography, 7th ed. by Tarbuck and Lutgens, 2002,...

Oct2110 03:48 PM
Studiot

9 
2,754 
I am looking for educational derivation( or any available and detailed) of the key principle of statistical...

Apr2308 01:28 AM
bilha nissenson

12 
2,492 
When a cue ball is driven into another ball, it is either not accelerating or decelerating at impact. It has momentum...

Aug911 12:14 AM
rcgldr

1 
1,170 
If I combine 2 laser beams of different wavelengths, would I get a beat frequency of the difference between the 2...

Oct1511 02:46 PM
xts

2 
1,215 
I went for a run and measured time and distance. I wanted to estimate how many calories I used.
Suppose a ran a...

Dec1307 07:17 AM
Shooting Star

1 
2,553 
Hi
I am new to this forum. I am an amateur blacksmith/machinist/all around tinkerer. I took a class with a...

May2814 07:33 AM
Nugatory

4 
223 
Okay, first a brief intro. I studied math/physics extensively as an undergrad...but that was over 10 years ago now. ...

Sep310 09:08 PM
Bill M

2 
932 
Hello,
I'm trying to figure out a method of calculating the work done by friction on an object sliding down a...

Feb1711 04:32 AM
tinytim

14 
3,977 
If the crest of one light wave meets the trough of another light wave of the same frequency and intensity they...

Feb1708 02:04 PM
Jakell

1 
3,936 
How do I calculate the force (in newtons) acting on a conductor moving through a magnetic field? This is in relation...

Apr2407 06:29 AM
bill nye scienceguy!

6 
1,762 
does a high dryness fraction mean that the steam is dry or wet?

Nov2707 09:52 AM
bill nye scienceguy!

4 
18,745 
i need to find max shear stress at a point on a plate (with a hole) under tension. i found using experimental data the...

Dec607 10:54 AM
FredGarvin

1 
4,358 
if there is a decrease in pressure at constant temperature will there be an increase in entropy?

Dec2007 04:31 PM
Andrew Mason

7 
5,921 
what exactly is the cutoff ratio, in physical terms?

Jan208 03:57 PM
brewnog

2 
3,992 
I want to calculate the temperature on the outside of a pipe which has a heated fluid flowing through it. If I know...

Jan2309 06:14 PM
henxan

2 
7,962 
I am in the final year of an MEng in mechanical engineering, working on my Final Year Project. I've been designing a...

Nov1709 08:19 AM
bill nye scienceguy!

0 
579 
I guess this question applies to deriving empirical equations from any data set but in my engineering studies I've...

Mar2310 02:16 PM
Naty1

1 
2,528 
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 
718 
Although continuity equation is often part of fluid mechanics, does it have an application in air flow? For example,...

Jun2013 07:31 AM
boneh3ad

3 
598 
Hi,
I do not know how to drive an experession for energy loss of damped oscillator.I know that:
X(t)=A...

Oct305 08:14 PM
Bill12

2 
4,817 
I have an application (clothes washer) which requires a drive design such that:
The drum contains 170 lbs of water...

Nov1709 03:50 PM
Bob S

8 
838 