Imagine for a moment that there is a hot air balloon which has a strong shell forming the balloons shape rather than one made from material and it weighs the same as a...

Air density, vacuum and gravity]]>

Voltage in a Circuit]]>

Friends! Please explain in simpler...

Changing Identity]]>

Using the Maxwell-Boltzmann equation above, there is an example in my book (Giancoli 4th edition p. 481) where they use this to find the average velocity. I understand that it would just be the sum of all...

Average Speed for Maxwell's Distribution of Molecular Speed]]>

any...

calculating force on a punching bag?]]>

potential at any point r=V

While source charge is Q...

How to find potential ENERGY between two point charges?]]>

I would like to evaluate the required work to create a 1 T field with a permanent magnet. I saw a few formulas on the internet, but I don't know how to use them correctly. The main one are

[itex]B={{\mu }_{0}}\left( H+M \right)[/itex]

[itex]{{W}_{mag}}=\frac{{{B}^{2}}}{2{{\mu...

Work done by permanent magnet]]>

Thank you]]>

There was a question

In figure two points A and B are located in a region of electric field.,The potential difference ##V

1-positive

2-Negative...

potential difference: positive or negative?]]>

Possible non-burning visible beam mock-up?]]>

I am just trying to understand the output of a sound spectrum analyzer. There are three dimensions

1) Time

2) Frequency

3) Volume (db)

I am confused about few things here:

1) How should I perceive the volume dimension here?

2) Why are the db values negative here and w.r.t what reference...

Understanding a sound spectrum analyzer output]]>

Proof/Explanation to why bullet hits the apple]]>

I've got a serious problem. Generally I know why current flows (free electrons and voltage). But some days ago I was considering about regular battery and electrical circut.

Free electrons in wire flow along circut, ok, that's fine and understandable. But how does battery...

Electric current]]>

What I mean is that, say we start with a 'starting point' equation, in this example Ficks law of diffusion (wikipedia:):

[tex] J = -D \frac{\delta...

Understanding the physical meaning of multiplication, etc]]>

difference between IR and heat]]>

Is the speed of light constant at all speeds? So will the speed of light (3 x 10^8 m/s) be the same if a person was travelling at 1000 km/hr and if they were stationary.

Thanks]]>

I am planning to write something along these lines, but I want to see if anyone can tell me if I'm missing something here:

"Imagine a rod that is connected in a frictionless and weightless...

Instantaneous communication]]>

Time and matter, is there a smallest unit?]]>

How we measure time]]>

I am an artist. I am looking for an answer on the nature of sight. What is the best explanation for how sight occurs. Do we see a 3D world illuminated by 2D photons? Can we...

2D or 3D?]]>

In this paper...

What is a phase transition in the context of an ising glass?]]>

I want to ask how do I extrapolate a correlation from a bunch of numbers. I did and experiment on gyroscopes, and have three kinds of data, w1, w3 and F_t, the later two can be used to calculate L3 and T_g. My...

How do I analyze data?]]>

I understand that the equation to calculate the maximum height of a projectile (ignoring wind resistance) is

H

Maximum height of ball with changing acceleration]]>

However, I know that when the paddle is moving in one direction, when the ball collides with the moving paddle, the ball should bounce of with a...

Momentum of a ball]]>

I have been pondering and pondering on how this is actually possible. If you think about it, the buckets are actually holding down the table....

Floating Table (With Buckets)]]>

If suddenly an object goes about 689 degrees farenheit (365 degrees celsius) in a room, about which perimeter would human life be impossible ?]]>

is there a possible or a certain arrangement of prisms , lenses and mirrors that can be made in order to combine numerous less...

Combine lasers to make a single strong beam]]>

Mach 3 aerodynamic drag]]>

I was told that the numerical Angular Spectrum Method is only valid low numerical aperture values, I want to know the boundary of this value.

Thank you in advance.]]>

the given answer:

thin, because a thin convex mirror does not form multiple images

can someone please explain to me why a thin spherical mirror does not form multiple images...

thick convex mirror or a thin one for the anti-theft mirror?]]>

What is Gravity?]]>

Was metric based on the universe (physics) or is the universe somehow based on metric?]]>

So, I'm new here. And I'm of 13 years of age. I am a programmer in a platform called "ROBLOX". I wanted to create my own Animator within that platform, using Inverse Kinematics. However, searching through the web, everything is just so complicated to me. I don't seem to understand the...

Inverse Kinematics: The Math]]>

My question is what are the necessary setups?

I know that I would need a strong magnet like neodymium magnet. But, i have no idea about the formula. Lets say i...

Magnetic Levitation Formula]]>

Heat transfer through finite temperature difference is known a irreversible process because heat cannot be transferred from cold to hot temperature without doing any additional work. But, how this transfer affect the efficiency of the system? How this heat transfer decrease the amount of...

Heat transfer through finite temperature difference]]>

Not sure if this case is also related but when I attach a coin sized metal onto a piezoelectric material of a smaller size, the resonance frequency range actually goes up (from...

Resonance frequency increasing with mass??]]>

I want to make a cable-driven reduction system between a threaded rod (pinion) and a larger threaded cylinder. Because of string walking, the string between the two has to stay at all times straight, parallel to the ground so that...

parallel string walking between two threaded cylinders?]]>