Golden Tortoise Beetle Transforming From Gold To Red

You and I had a fight recently.

Today’s doodle: Torvosaurus tanneri for some signage at Eccles Dinosaur Park. Happy #FossilFriday!

Spider in amber. It’s amazing! 🕷

More fossils from the Lapworth Museum of geology!

Top to bottom:

- Cambrian (Marrella splendens, Hurdia victoria, trilobites)

- Devonian fish (Pteraspis, Drepanaspis, Bothriolepis, Cephalaspis)

- Permian (Dimetrodon, Mesosaurus)

- Quarternary (Smilodon)

A short note on how to interpret Fourier Series animations

When one searches for Fourier series animations online, these amazing gifs are what they stumble upon.

They are absolutely remarkable to look at. But what are the circles actually doing here?

Vector Addition

Your objective is to represent a square wave by combining many sine waves. As you know, the trajectory traced by a particle moving along a circle is a sinusoid:

This kind of looks like a square wave but we can do better by adding another harmonic.

We note that the position of the particle in the two harmonics can be represented as a vector that constantly changes with time like so:

And being vector quantities, instead of representing them separately, we can add them by the rules of vector addition and represent them a single entity i.e:

                                                  Source

The trajectory traced by the resultant of these vectors gives us our waveform. 

And as promised by the Fourier series, adding in more and more harmonics reduces the error in the waveform obtained.

        Have a good one!

**More amazing Fourier series gifs can be found here.

Arte conceptual de Legacy of Kain: Defiance Vol. 02

These are just amazing!

Moth is not a four-letter word for this UK knitter! | KnitHacker

Max Alexander‘s knitted moths are incredible – I am simply blown away. LOVE! I also like the irony of using wool to knit moths – normally that combination strikes fear into the heart of every knitter/crocheter I know!

African Cherry Spot Moth 

Knitted Merveille du Jour Moth 

Tatargina Picta Moth 

Peach Blossom Moth

The amazing history of Pi. 

Beautifully designs from Circle.

Beautifully designs of Spirograph are the gifts that I want to send to Pi on Pi’s Day. They are created from circles, with geometric drawing tools - Spirograph.

Pi’s Family: 10,000 Digits Of Pi.

3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067982148086513282306647093844609550582231725359408128481117450284102701938521105559644622948954930381964428810975665933446128475648233786783165271201909145648566923460348610454326648213393607260249141273724587006606315588174881520920962829254091715364367892590360011330530548820466521384146951941511609… and more. These are the first 1,000,000 are listed here.

Happy Pi Day to you, Happy Pi Day to you, Happy Pi Day, Three Point One Four. Happy Pi Day to you. HAPPY PI DAY! :)……….

3/14/15.

That’s how a revolving fan works

This gif has been circulating throughout the internet for many years, and I am not denying it It’s pretty darn cool!

Although it gets the mechanism spot on, but it misses out on one of the most amazing part of the mechanism : the oscillation itself.

How does it oscillate?

                       Source

The oscillation is simple but ingenious. So, you see that pink rod? Yeah that is attached to v - type wedge, like so:

89 is a pin. And that pin is constrained to oscillate between the two wedges. The angle of oscillation is primarily between 40-100 degrees.

It is this wedge that controls the oscillation.

Why does it oscillate?

The oscillation is due to an eccentric round cam present under the yellow gear. ( seen in animation too )

An eccentric cam

The rotation of this cam induces a torque which causes the linkage ( the pink rod ) to sweep across the plane.

Important Note

I understand that this explanation is not exactly the finest. But this mechanism has not been explored anywhere else on the Internet .This is what i could reckon of the Patent.

If you have a better explanation/sources/anything at all then please reblog it with this post, that way everyone wins. It is our humble request.

Have a good day!

When Trilobites Ruled the World

infographics by The New York Times

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