I just need help with the calculations. Once I know how to do the calculations I can just translate that into java code.

View attachment 148331]]>

On the way back to the table, the waiter ponders on how he is going to split $5 three ways.

No problem, he thinks. "They think the total...

Another math problem (fun)]]>

Math is fun again.]]>

Since at any given point in time the filtered signal is the weighed average of many previous points, whatever change the amplitude of a constant frequency signal is irrevocably lost.

For instance, if I filter a simple sine wive that is within my passbound limits, I still get the same wave as a result. Okay. But if the signal is, say, one period...

Demodulating a filtered signal]]>

If the following input signal (which is made up of 2 components) is applied to the low pass filter:

Using superposition the out signal can be determined. If we assume that ,

Multiply input directly to the tranfer function/frequency response]]>

Solve for Y = 0 with proof.

Rules:

Don't post the answer if you already know it. The challenge is to figure it out from scratch. Who will be first ?

It will be interesting to see how different people approach the problem.

WARNING

Those of faint heart best not indulge.

This puzzle is way harder than it looks.

It was first solved in the 1600's and considered one of the greatest achievements.

I started looking at it 5 years ago, with a few clues, and only worked it...

Cubic Solution Puzzle]]>

Not surprisingly, the more games that constitute a match the greater the likelihood that the better team will win the match. But if the teams are almost evenly matched, it can take a large number of games before the likelihood that the better team will win the match becomes...

How many games should be in the match [rec puzzle]]]>

Let's begin with this simple equation: ν = A sin θ. I'm not sure you could say it describes the signal. What I am sure about is that if someone sets a question and asks me to calculate ν, as long as I'm told the angle (theta) I can do it. If , in a question, A is 200V (Voltage at peak:...

Describing a sinusoidal signal mathematically and it's uses.]]>

i have been given the following:

Voltage = 100v phase angle 0° at 20hz

Current = 1.5A phase angle -30°

Capacitor = 50μF

any help would be much appreciated

many thanks]]>

You have 12 coins and a balance scale. One of the coins is counterfeit. You can use the balance scale exactly three times, placing however many coins you want in the pans. After those three weighing, you have to determine which coin is counterfeit and whether it is heavy or light.

There are no tricks. Eleven coins weigh the same and one coin is different,...

Ternary Notation: Revisiting 12 coins [Mathematical Recreation]]]>

Imagine a string of 0's and 1's (call it 's') and the reverse of the string (call it 'r'). For instance

s = 1100

r = 0011

Now, interpret 's' as a base-2 value and interpret 'r' as a base-3 value.

s = 1100 (base-2 = 12)

r = 0011 (base-3 = 4)

If 's' is a string such that 's' is divisibly by 3 but 'r' is NOT divisible by 2, then we put 's' into a collection of strings and call that collection the language L....

Shortest strings having divisibility properties in both directions.]]>

If they play a “best of 3” match, how often can we expect player X to win?

How about if X’s odds of winning a game are .70 or .80 or .90?]]>

The length of bolts made in factory Z is normally distributed, with a mean length of 0.1630 meters and a standard deviation of 0.0084 meters. The probability that a randomly selected bolt is between...

Potentially fun math problem]]>

Now spiral a wire about this N times, evenly spaced.

What is the length of this wire?

My approximation is probably close enough, but I wonder if there is a simple answer to this.

(Note: I am NOT planning how to light my Christmas Tree. No, not me.)]]>

Look to attached image.

In the upper plot there is the plot of ALL SIGNAL SAMPLES.

In the lower plot there are many WINDOW SAMPLES (separated by vertical lines); thus for every sample in window width, we compute SIGNAL SAMPLES .* WINDOW SAMPLES.

Then we JOIN all previous products and get the FULL WINDOWED SIGNAL; on this finally signal we calculate Y = fft(FULL WINDOWED SIGNAL, N fft points)

Is the...

Windowed fft: how windowing is practically applied at overall data?]]>

I started working on the resistor cube problem that we started thinking about in the resistor grid thread. Here are some results:

Code (Text):

- Resistor Mesh Cube
- ------------------
- N V R
- 1 4.000000 8.333333
- 2 3.255814 10.238095
- 3 2.967581 11.232493
- 4 2.813628 11.847100
- 5 2.718043 12.263726
- 6 2.653020 12.564298
- 7 2.605965 12.791168
- 8 2.570354 12.968384
- 9 2.542474 13.110588
- 10 2.520060 13.227196
- 20 2.418082 13.785033...

View attachment 140628

View attachment 140629]]>

I am trying to find an expression for the output voltage of my Royer oscillator. I have attached the oscillator as a file to this post.

I understand how the system works in practice and theory. However I need some help finding an expression for the voltage across L4.

Thanks!

Kasper]]>