09 May '15, 5am

Hackaday Prize Entry: An EM Drive

There’s no mystery about the fact that photons (including microwave photons) have momentum. You can use a laser as a space drive… and it would work better than this turkey because all of the photons are (more or less) going in one direction and none of them are being reabsorbed and turned into heat. The amount of thrust produced per unit energy is tiny (thrust is power divided by the speed of light). It’s reasonably easy to demonstrate that any drive system that purports to do better than that without using reaction mass violates conservation of energy in any region of curved spacetime… and all spacetime is curved. Here’s how you do it. First, realize that curved spacetime just means a gravity field. Let’s start with Earth’s, since we live here. I’ll show a specific case then use induction to prove it’s universal. Let’s use round numbers… g = 10 m/s^2 and a drive that prod...

Full article: http://hackaday.com/2015/05/08/hackaday-prize-entry-an-em...

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Hackaday Prize Entry: Open Source Diesel

hackaday.com 10 May '15, 5am

You cant change the compression ratio, not without somehow moving one crank in or changing the length of the connecting ro...

Live Now: 2015 Hackaday Prize Worldwide: LA

hackaday.com 09 May '15, 6pm

Right now we’re throwing a huge workshop, meetup, and hackathon in Pasadena . Events include a ‘Zero to Product’ workshop ...

Hackaday Meetup NYC

hackaday.com 09 May '15, 5pm

This flight data recorder keeps relevant data on a loop of mylar tape. We didn’t crack into that part of the black box, bu...

Hackaday Prize Entry: A Better KVM Switch

hackaday.com 06 May '15, 2am

ok while this is not the exact solution i’m personally looking for, this is a great development. KVM switches are still so...

Hackaday Links: May 10, 2015

hackaday.com 10 May '15, 11pm

Here’s a cool crowdfunding campaign that somehow escaped the Hackaday Tip Line. It’s a remote control SpaceShipOne and Whi...

Hackaday Prize Entry: Junkyard Fuel Cell

hackaday.com 12 May '15, 5am

You need both platinum and the expensive PEM for a fuel cell to work. The specific DuPont product typically used is Nafion...

Hackaday Prize Entry: A 7805 Replacement

Hackaday Prize Entry: A 7805 Replacement

hackaday.com 14 May '15, 5am

I made them back in 2008 specifically for my UPS project (also on hackaday.io). I have a few other types (boost, isolated)...

Hackaday Prize Entry: A Fixation On Nitrogen

hackaday.com 03 May '15, 8am

The real problem is too many people, for the limited resources on one planet. And we can’t import matter from other planet...

Hackaday Prize Entry: A Low Cost, Open Source MRI

hackaday.com 04 May '15, 11pm

I’m the project creator and a Canadian who has been living in the US for over four years. My mother was also diagnosed wit...

Hackaday Prize Entry : Impact – A Head Concussion Monitor

Hackaday Prize Entry : Impact – A Head Concussi...

hackaday.com 11 May '15, 5am

A lot of young athletes who get concussions each year go undiagnosed, leading to brain injury. [Hunter Scott] is working o...

Hackaday Prize Entry: Building A Car, From Scratch, Out Of Foam

Hackaday Prize Entry: Building A Car, From Scra...

hackaday.com 30 Apr '15, 8am

Want an impressive example of what a few people can do in a garage? How about building an electric car, from scratch, star...

Field Trip! Hackaday Visits Adafruit Industries

hackaday.com 08 May '15, 6pm

I am tired of this “we need women” in certain fields, because some people care more about statistics and “feel good” ideol...

Gotta have 'em.

finishline.com 15 May '15, 1am

Promotional offer only valid on eligible items. Look for the "Qualifies for Free Shipping" text on eligible products. Othe...

Hackaday Prize Entry: A $100 CT Scanner

hackaday.com 15 May '15, 5am

What do you do when you’re dad’s a veterinarian, dumped an old x-ray machine in your garage, and you’re looking for an ent...

Hackaday Prize Entry: The MultiSpork

hackaday.com 21 May '15, 5am

This is a cool idea — and I like to see people trying new things to see what works, but I wish they were using better sili...