Currently I am focused on Section 2.2 Free Modules ... ...

I need some help in order to fully understand the proof of the equivalence of (1) and (3) in Proposition 2.2.3 ...

Proposition 2.2.3 and its proof reads as follows:...

Free Modules, Bases and Direct Sums/Products]]>

son and father and granpa have same value for their birthday (except the year ostensibly)

father is nine times the son's age now. calculate the granpa's age now.

clues

- five years ago, grandpa was 32 years older than what the...

algebra age riddle word problem]]>

There are various ways to stack individual exposures. A number of programs are available ranging

from free to quite expensive ... several 100 US$

free = DSS - Deep Sky Stacker...

Deep Space Imaging and stacking images for less noise]]>

Please give me a clue, I don't understand, how to find the magnitude of ##I_{ab}##?

Sorry for...

About capacitor -- how can current flow "through" it?]]>

High school student struggling with Honors Chemistry]]>

thanks]]>

This because the distance is shorter for you in the spaceship and light speed is constant.

Example: A star 100 ly....

Consequences of length contraction]]>

International Physics Studies Program (IPSP) University of Leipzig program review?]]>

Derivative of an integral help]]>

"Braking distance refers to the distance a vehicle will travel from the point when its brakes are fully applied to when it comes to a complete stop."

I'd like to know...

Braking Distance, Skids & ABS]]>

This is the question as it was given...no other data was given.

Obtain Fourier's heat conduction equation in three dimensions in an infinite medium in steady state.What modifications will be required in case of a finite body?...

Fourier's heat conduction equation]]>

I know this has been asked a lot, I read through ZapperZ's excellent essay on the subject, his post, and many other related threads. But I'm still somewhat confused.

Now I

Second Bachelors in Physics, Masters or PhD?]]>

If cosθ=(3/5) and 0<

determine the value of sin[

Attempt:

θ=0.927295218

real answer = 0.992820323, -0.39282

How do i find the second value, all i can find is

sin[θ+(pi/6)] Multiple values???]]>

I am trying to build (or at least conceptually) design a diy autonomous lawnmower.

I want to add an automated grass cutting height mechanism.

I have never worked with lawnmowers but through basic googling know that most lawnmowers have simple mechanisms in wheels to change cutting height....

Mechanism for height adjustment of rotating body]]>

.....

Okay, so in the last Game of Thrones episode, a massive twist involving what appears to me to be a bootstrap paradox occurred. I was wondering what anyone who saw thought about it and for those who did or didn't whether or not it makes...

Hodor bootstrap Paradox? SPOILERS FOR GAME OF THRONES]]>

Our Beautiful Universe]]>

(n/2)!/[(n+2)/2]!

I get,

2[n(n-1)]/2[(n+2)(n+1)n(n-1)]

cancelling the 2[n(n-1)]

leaves me with 1/[(n+2)(n+1)]

However, Wolfram Alpha tells me this can be simplified as 2/(n+2) and I don't see that.

Thanks]]>

Here is the last page of part 4. https://www.physicsforums.com/threads/random-thoughts-part-4.786642/page-201]]>

Calculating wheel torque from engine torque]]>

OrCad Capture Cis. Unconnected pin, no FLOAT property or FLOAT = e]]>

It is in Warwickshire England

It moves in the wind

A box one keeps valuables...

All around the world]]>

When two reference systems move relative to each other, space becomes shorter in them, as seen from the other system.

Gravity and acceleration are indistinguishable.

The...

Is acceleration responsible for shortening of space]]>

Two dimensional plane equal absolute nothing]]>

A 4-pole, star-connected, 50 Hz, 11kV, 40 MVA turbogenerator, with a synchronous reactance of 0.8 p.i., is connected to a power network. This power network can be represented by 11-kV infinite bus with a series reactance of j 0.5 Ω. A voltage regulator adjusts the...

Synchronous generator phasor diagram]]>

I would like to know if f✶g is a differentiable function of x.

If, for example, g(t) = 1 for t ≥ 0 then f✶g(x) =...

Differentiability of convolution]]>

What kinds of dangerous/parasite animals are in your area?]]>

I am working on an old scooter with small displacement (150cc, with about 9.6:1 compression ratio). After rebuilding the engine, I figured I have to put in a much bigger piston 60mm compared to the original 58mm...

Vacuum fuel pump problem]]>

Can I think of this in terms of the fact that the boundary conditions for the solution of the TISE are fixed, such...

Energy levels generally invariant under fixed V, changing T]]>

I = C*(dV/dt)

V = IR, so I = V/R

V/R = C*(dV/dt)

(V*dt) = R*C* dV

Integrate both...

Capacitance vs. Resistance Proof]]>

Magnitude-5.3 earthquake hits Japan's Fukushima

http://www.usatoday.com/story/news/world/2013/09/19/japan-fukushima-nuclear-plant/2835493/

I am trying to learn to fly an RC model (Bixler 2, training/beginner level which I assume means "stable, easy to fly"). What is happening is that when I use ailerons to list the model and turn, it turns but then starts...

mechanics of flight]]>

Kale's Contracting disc]]>

θ = sinθ or θ = θ?

Let's say if the angle of displacement = 45° do I just plug 45° as θ into the equation below or should it be sin(45°)?

Or is it θ = S/R ?

ω

Need help with Newtonian equations with angular momentum]]>