Some Things I’ve Learned While Studying In Quarantine

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Hi Steph! I love your blog and your fic recs! I was wondering if you could please help me find a fic I read a while ago but lost. It's post-Reichenbach, where I remember it takes ~42 days for "the fog to lift from John's mind" and he realises what Sherlock meant by his 'note', and John works on clearing Sherlock's name, then moves to a lil house by the sea, and patiently waits for Sherlock, who shows up after a year and a half, I think? Please, it's driving me crazy aha!

Hey Nonny!

Ooof, I have no idea which fic this is, but it sounds vaguely familiar... anyone able to help me out with this one??

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Hey @infinitesimally-smart, have some shapes

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february 4, 2018 — rewriting my semantics notes into more cheat sheet looking things!! ╭( ･ㅂ･)و"))

♫ EVERYTHING FROM THE PERFECT RED VELVET

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told my project partner all she had to do was write the sql script following the logical schema i drew so carefully

this is what she came up with 🤦‍♀️:

where are the foreign keys, where are the semicolons, and why the hell are there STRINGs in an sql script

do i yeet her out of the window or do i yeet myself out of the window

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Planets i learned about via youtube while procrastinating my english essay

Planet 55 Cancri e is basically a giant diamond. like the planet is a diamond. and it would be worth $26.9 nonillion

Planet Gliese 436 b is an ice planet that is constantly on fire do to its close proximity to its parent star. the ice doesn’t melt bc the planet’s gravity is so strong it physically prevents the ice from melting

Planet HD 189733b rains sideways glass…. constantly

Planet J1407-B has planetary rings that are 200x the size of saturn. if saturn’s ring were as big as J1407-B’s we’d be able to see them with our naked eye from earth AND they would dominate our sky and look larger than a full moon

Planet Wasp-12b rotates so close to its parent star that its slowly being consumed by the it

Planet Gliese 581c is one of the candidates for a planet that can support life however it orbits a tiny dwarf star and is tidally locked so one side is constantly subject to immense sunlight while the other is constantly in darkness. there’s a small area of the planet however, that is just the right temp to support life. u just can’t step out of said area. the skies are red and the plants would have be a black color instead of a green bc they would use infrared light for photosynthesis. (a message was actually sent to the planet in 2008 in hopes that there’s life on the planet but the message wont reach the planet until 2029).

Planet GJ 1214b is a water planet nicknamed “water world” is has no land at all and the water is so deep it goes down miles all the way to the planet’s core.

Planet Wasp-17b is the largest planet discovered thus far. its so large its existence contradicts our understanding of how planets are formed. and it has a retrograde orbit, so it orbits in the opposite direction of its parent star.

Planet HD 188753 has 3 suns you should have triple shadows and there would be almost daily eclipses. and no matter which direction u face on the planet u would always see a sunset

Planet HD106906b is the loneliest planet discovered thus far. its known as “super jupiter” bc its 11x bigger than jupiter. it orbits its parent star at a distance of 60 billion miles (which is v strange) hence why its the loneliest planet.

Planet Tres 2b is the darkest planet known. it reflects less than 1% of light (it reflects less light than coal and black acrylic paint). the tiny part of the planet that does reflect light is red making the planet glow a dim red.

The tails of Comet NEOWISE!! Comet’s usually have 2 tails that always point away from the Sun.

Here, NEOWISE’s blue ion tail on the left points directly away from the Sun and is pushed out by the flowing and charged solar wind. Structure in the ion tail comes from different rates of expelled blue-glowing ions from the comet's nucleus, as well as the always changing structure of our Sun's wind.

The other tail, the dust tail, is pushed out by sunlight, but curves towards its orbital path as heavier dust particles are better able to resist this light pressure. Comet NEOWISE's (Comet C/2020 F3) impressive dust-tail striations are not fully understood, as yet, but likely related to rotating streams of sun-reflecting grit liberated by melting ice on its 5-kilometer wide nucleus.

Image Credit & Copyright: Zixuan Lin (Beijing Normal U.)

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You’re going to receive GOOD NEWS this week.

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Propagation of Error

When I first started in physics, I was utterly clueless about propagating error. After three years of college, I have a better grasp of it and feel more comfortable using it in the lab. Have a look if you’re having trouble with error propagation!

Error and Uncertainty

Error: an unknown quantity in the realm of the state of nature

Uncertainty: a parameter in the realm of our state of knowledge about nature

Type A uncertainty: statistical in nature (an example of this would be if you were launching an object 15 times and recorded each distance)

Type B uncertainty: not statistical in nature (an example of this would be a digital reading on a scale - no matter how many times you put the same object on the scale, you will get the same reading)

Random vs Systematic Error

Random Error

environmental fluctuations

equipment noise

natural processes

Systematic Error

environment: fixed beyond a relevant parameter

measurement technique: assumptions, experimenter bias

equipment with an offset or using equipment beyond its limits

uninformed choices

You can reduce random error by taking more measurements.

You can reduce systematic error through thoroughness, properly calibrating equipment, reading manuals, and ensuring reproducibility. 

Basic Error Propagation

This is the standard equation for error propagation:

This represents the uncertainty in the measurement of some value x. Suppose you are measuring this value based on this equation:

You took three measurements, a, b, and c, and plugged them into this equation to get x. However, there is some uncertainty associated with each of these three values. Let’s say you measured a on a scale, b on an oscilloscope, and c with a ruler. There is uncertainty associated with all of those measurements. When you’re reading the scale, you read it as 15.45g. Let’s assume there is an uncertainty of 0.01g in that reading. Similarly, you read your oscilloscope to be 3V, and there is an uncertainty of 0.05V. You read your ruler to be 3.45cm, and there is an uncertainty of 0.05cm. We now have our uncertainties for the three values:

a = 15.45g +/- 0.01g

b = 3V +/- 0.05V

c = 3.45cm +/- 0.05cm

The other aspect of the uncertainty equation is taking the partial derivative. Those are the dx/da and dx/db parts of the equation. We will take the partial with respect of each term. 

The partial derivative of the equation for x with respect to a is 2a2

The partial derivative of the equation for x with respect to b is 2

The partial derivative of the equation for x with respect to c is 4.5

Now, we can plug into our equation:

Your uncertainty in your measurement for x is +/- 22.86.

I hoped this helped you if you’re struggling with uncertainty! 

I believe in free education, one that’s available to everyone; no matter their race, gender, age, wealth, etc… This masterpost was created for every knowledge hungry individual out there. I hope it will serve you well. Enjoy!

FREE ONLINE COURSES (here are listed websites that provide huge variety of courses)

Alison 

Coursera

FutureLearn

open2study

Khan Academy

edX

P2P U

Academic Earth

iversity

Stanford Online

MIT Open Courseware

Open Yale Courses

BBC Learning

OpenLearn

Carnegie Mellon University OLI

University of Reddit

Saylor

IDEAS, INSPIRATION & NEWS (websites which deliver educational content meant to entertain you and stimulate your brain)

TED

FORA

Big Think 

99u

BBC Future

Seriously Amazing

How Stuff Works

Discovery News

National Geographic

Science News

Popular Science

IFLScience

YouTube Edu

NewScientist

DIY & HOW-TO’S (Don’t know how to do that? Want to learn how to do it yourself? Here are some great websites.)

wikiHow

Wonder How To

instructables

eHow

Howcast

MAKE

Do it yourself

FREE TEXTBOOKS & E-BOOKS

OpenStax CNX

Open Textbooks

Bookboon

Textbook Revolution

E-books Directory

FullBooks

Books Should Be Free

Classic Reader

Read Print

Project Gutenberg

AudioBooks For Free

LibriVox

Poem Hunter

Bartleby

MIT Classics

Many Books

Open Textbooks BCcampus

Open Textbook Library

WikiBooks

SCIENTIFIC ARTICLES & JOURNALS

Directory of Open Access Journals

Scitable

PLOS

Wiley Open Access

Springer Open

Oxford Open

Elsevier Open Access

ArXiv

Open Access Library

LEARN:

1. LANGUAGES

Duolingo

BBC Languages

Learn A Language

101languages

Memrise

Livemocha

Foreign Services Institute

My Languages

Surface Languages

Lingualia

OmniGlot

OpenCulture’s Language links

2. COMPUTER SCIENCE & PROGRAMMING

Codecademy

Programmr

GA Dash

CodeHS

w3schools

Code Avengers

Codelearn

The Code Player

Code School

Code.org

Programming Motherf*?$%#

Bento

Bucky’s room

WiBit

Learn Code the Hard Way

Mozilla Developer Network

Microsoft Virtual Academy

3. YOGA & MEDITATION

Learning Yoga

Learn Meditation

Yome

Free Meditation

Online Meditation

Do Yoga With Me

Yoga Learning Center

4. PHOTOGRAPHY & FILMMAKING

Exposure Guide

The Bastards Book of Photography

Cambridge in Color

Best Photo Lessons

Photography Course

Production Now

nyvs

Learn About Film

Film School Online

5. DRAWING & PAINTING

Enliighten

Ctrl+Paint

ArtGraphica

Google Cultural Institute

Drawspace

DragoArt

WetCanvas

6. INSTRUMENTS & MUSIC THEORY

Music Theory

Teoria

Music Theory Videos

Furmanczyk Academy of Music

Dave Conservatoire

Petrucci Music Library

Justin Guitar

Guitar Lessons

Piano Lessons

Zebra Keys

Play Bass Now

7. OTHER UNCATEGORIZED SKILLS

Investopedia

The Chess Website

Chesscademy

Chess.com

Spreeder

ReadSpeeder

First Aid for Free

First Aid Web

NHS Choices

Wolfram Demonstrations Project

Please feel free to add more learning focused websites. 

*There are a lot more learning websites out there, but I picked the ones that are, as far as I’m aware, completely free and in my opinion the best/ most useful.