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Again, for some odd reason, people...

Apr2211 05:26 AM
ZapperZ

1 
46,225 
Why is the total energy of an elliptical orbit given by:
E_{tot}=\frac{GMm}{2a}
Where a=semi major axis.
I agree...

Feb1810 06:52 PM
shnav34

5 
5,901 
Good afternoon,
First of all, this is not a homework question, but I'm not sure whether it should be posted on the...

Feb1910 12:18 PM
pc2brazil

13 
1,933 
I'm wondering if it make much difference if they used silver instead of copper wire in electric generators? Also, how...

Feb1810 09:25 AM
GRDixon

4 
765 
I have a Question:
suppose we have a satellite (m=400kg, V0=40m/s) and we want to put it in a 1000km orbit...

Feb1910 02:40 AM
smhni

3 
2,414 
I was told that Hooke's Law (F=kx) only accounts for small displacements. But for some objects the displacement can...

Feb2010 09:45 AM
Mapes

1 
1,644 
according to first law of thermodynamics,q=w for a reversible isothermal process.this means all the energy absorbed is...

Feb1810 08:24 AM
Mapes

1 
691 
Hi everyone,
I am new to the physics forum. I have been trying to find out relationship between the heat loss by a...

Feb1710 03:04 PM
bisseychor

0 
3,870 
I noticed that the relations in mechanics can be seen like:
1) assume conservation of angular momentum
2) from...

Feb1710 12:35 PM
Gerenuk

0 
500 
In electrostatic case, Gauss's law can be derived from Columb's law, so we can regard experimental evidence for...

Feb1710 12:14 PM
kof9595995

2 
2,011 
My question is seemingly simple.
Let us suppose that we had an unbreakable/inflexible rod whose length was 11.8...

Feb1810 08:11 AM
A.T.

4 
1,125 
I know for spherical or plane EM wave, there's relation E=cB, and we can prove it by the explicit expression of these...

Feb1810 01:19 PM
kof9595995

5 
7,705 
F=ma and w=mg; with acceleration = gravity, then Force = weight.
lb is a mass
lbf is a force
kg is a mass
I...

Feb1710 04:41 PM
D H

13 
2,020 
Given: a point charge (at rest at the Origin at time t=0) with a constant acceleration in the +x direction. ...

Feb1810 09:42 AM
GRDixon

1 
658 
Hi,
I am trying to model the magnetic field from two permanent magnets using Matlab, although my particular problem...

Feb1710 02:19 PM
stephenx_86

0 
1,496 
I am an ME with my years of heat transfer approx. 20 years back. I have a 3' x 7' insulated sub floor that utilizes an...

Feb1710 02:44 PM
sdlamb100

1 
627 
Hi, if the shear stress on an element in a solid is SAy/bI, where S is the shear force and y is the distance from the...

Feb1810 09:40 AM
milan666

7 
3,635 
Hi
Are the two (attached) circuits equivalent?
Also, what if any are the relation between the voltages? (ie....

Feb1710 05:04 PM
saunderson

1 
678 
Edit: Apparently Coulomb's law only holds for electrostatics... in that case I understand that this problem is...

Feb1710 07:12 PM
torquil

1 
947 
In some books I have seen:
\oint \mathbf{E} \cdot d\mathbf{s}=0
Since the Electric Field is meant to be...

Feb1710 09:32 PM
elect_eng

3 
631 
Dear Forumers,
As a nonEnglish speaker, I am confused about absorbance and absorptance. I found some definitions...

Feb1810 03:06 AM
Telmerk,the Magician

0 
1,751 
I would I go about determining the magnetic field of a bar magnet experimentally? Any ideas?

Feb1910 10:28 PM
Xyius

6 
2,787 
I was trying to study a way of estimating the capacitance of a capacitor in a kelvin water dropper experiment. Is...

Feb1810 03:49 AM
Mola

0 
2,882 
Hi,
Would appreciate any help anyone has for me.
I am building a physical pendulum of sort, which consists of a...

Feb1810 06:55 AM
I_am_learning

2 
1,971 
Hi,
I'm making laminar fluid flow devices and want to be able to calculate the velocity as a function of distance...

Feb1810 07:02 AM
stephenx_86

0 
10,664 
Can anyone please tell me if it is necessary for an adiabatic process to be isothermal? Please explain with example.

Feb2010 03:35 AM
Fightfish

5 
4,829 
Edit: Solved.

Feb1810 08:51 PM
dabananana

2 
1,280 
Imagine pushing a conducting loop (rectangular and rigid and perfectly conducting) into a magnetic field B. The loop...

Feb1810 09:52 PM
Bob S

1 
2,463 
How much does the phase and position of the moon affect the weight of an object on the surface of the earth? For...

Feb1810 08:59 PM
Janus

4 
5,219 
I am currently doing a material characterisation project and have performed a standard tensile test on a number of 304...

Feb2010 10:56 AM
junglep

3 
2,081 
A comet is in an elliptical orbit around the Sun. Its closest approach to the Sun is a distance of 5e10 m (inside the...

Feb1810 07:09 PM
shnav34

2 
1,150 
So I understand how to draw velocitytime graph "from" distance graph and accelerationtime graph "from" velocitytime...

Feb1910 03:32 AM
Stonebridge

1 
5,070 
I am having trouble understanding a building collapse. According to NIST, on 9/11 WTC7 collapsed after fire weakened...

Feb1910 11:58 PM
russ_watters

20 
2,632 
can someone plz explain to me physically how is it that
when i have an AC source and i measure Voltage on a resistor...

Feb2010 10:56 AM
DaleSpam

2 
2,646 
I am confused a bit about fact that there is a decrease in pressure as velocity is increased which is the principle...

Feb2010 04:37 AM
R Power

0 
1,384 
can someone please tell me what actually is lattice enthalpy. Is it energy released when one mole of bonds are broken...

Feb1910 03:17 PM
Sunny Kumar

1 
3,067 
I often read or hear people making a big deal that we speed along on the surface of the Earth at about 1,000 miles an...

Feb1910 08:18 PM
kanato

1 
457 
In a gas laser, an electron in the highest energy state absorbs photon for stimulated emission to occur, but now since...

Feb2010 04:27 AM
Claude Bile

1 
657 
i've been crossreferencing different sources as to the exact definition of the electromotive force, and i keep...

Feb2010 12:10 AM
arymaia

0 
1,897 
When you define \vec F(\vec r) = \phi(r') (\vec r)/r
Now U is usually denoted
U(\vec r) = \int_0^r \phi(r')...

Feb2010 02:58 AM
Nusc

2 
562 
So if you have an infinite sheet of charge at the location z = b, Poisson's equation reads
\nabla^2 V =...

Feb2010 07:30 AM
AxiomOfChoice

0 
1,099 