Monday, January 31, 2011

Freeze Motion Water Droplets

James at Work spoke to me the other day about a clever lab idea involving a strobe light and a special kind of water pump.



The idea is that the pump squirts a stream of water droplets on a regular basis which are synchronised with the mains power frequency. A stroboscope is then shone on the stream of droplets which depending on the flash frequency will freeze or slow down the motion of the droplets.

Below is a video of a similar apparatus at one of MIT's museums:


After more sleuthing on the internet I found a web page owned by Professor Derin A. Sherman he has a demonstration using the same principles.

Here is the video from Professor Derin's lab demonstration:




My Lab Demo:
Initially I was unsure as to what sort of pump would be available here in New Zealand however that was short lived. Espresso coffee machines use a oscillatory piston pump to achieve the 10 to 15 bar extraction pressure required. My mate Hamish aka b45h4 has a dead coffee machine sitting in his garage just begging to be "hacked" :D

Thats all for now - check back in a couple of days for pics and videos.

Friday, January 28, 2011

Torque and Moments

Introduction to Torque:



Introduction to Moments:


Thursday, January 27, 2011

Engineering Mechanics Statics

As promised here are a couple of youtube videos that may help you with the mechanics problems we're doing at present.

Introduction to Basic Trigonometry - Take a look at some of the other khanacademy videos while you're at it:




This one is part of a lecture series by IIT - It starts right from the beginning of mechanics:



Introduction to Vectors, Vector Addition and Multiplication: