Tek Tip 2sD #2 - Screw Head Design

First was the slotted screw - nobody really uses it now for good reason.

     

The next improvement in design was probably the Phillips head.  It's a lot better than the slotted screw above but if you've spent any time with that little x you know it tends to strip easily and damage the bit.

Teach Fzx Tuesday - Acceleration units

The units that we use for acceleration are stupid if we want our students to understand.

They constantly confound acceleration and velocity and forever forget the squared on that m/s.  A few years ago I switched over to "meters per second every second" and it has worked wonders.

Freaky Fzx Friday - The Birth of the Universe

Last week we took a look at some pictures of planets and stars to get some idea of how tiny we are. but we didn't even talk about our galaxy.

The Milky Way.  La Via Lactea.

The same light that takes 8 minutes to get here from our sun takes 100,000 years to cross the Milky Way.  It's 100,000 light years across and we are 8 light minutes from our sun.  The galaxy's big and we're in a peaceful part of it.

Tek Tip 2sD #1 - Screwdrivers

Which screwdriver would you choose to turn a stubborn screw?

Nope. If you're like my students, you chose the long one.  Sorry, Charlie.

Freaky Fzx Friday - You're Tiny

You're a bit smaller than Earth.  10,000,000,000,000,000,000,000 of you would give the same mass of the earth.  That's 10 raised to the twenty second power.

Here are some scale diagrams to help you understand:

Freaky Fzx Friday - Fictional Space Travel

Our solar system is a bit boring on the big screen.  It would take more than a month to reach even 10% the speed of light in a rocket.  That's engines blasting for 35 days.  And then engines blasting for another 35 days to stop you as you reach your destination.  Then you're stuck since you simply cannot carry that much fuel.

Seriously, we can't even get to Mars.

But movies and TV shows rely on science that doesn't exist.  Either stasis or cryosleep would be necessary to get us anywhere with conventional propulsion.

Cryosleep Imagination

Sometimes cryosleep gone wrong can lead to time travel if the pods keep running for centuries.  In this movie, Kirk and krew happen upon a centuries-old ship of supercriminals in stasis and they barely survive the confrontation.