Build-it, Leave-it, Teach-it

For the Build-it, Leave-it, Teach-it (BLT) project, SUNY Geneseo faculty and physics majors build physics demonstration equipment and discuss the best ways to present the demonstration in a classroom.  Physics teacher candidates then bring the piece of equipment to a local high school physics classroom and use it to teach a physical concept to the students.  The BLT unit is then left as a donation to that classroom.

 

BLT - The Race

In the Fall of 2011, we built "The Race".  In this demonstration, two identical steel balls are released from the same height on two vee-channel tracks.  They accelerate down identical slopes.  Then one ball goes uphill and downhill while the other ball goes downhill then uphill.  Which ball will reach the end of the track first?

(Click on the images below to see an enlarged version.)

BLT - The RaceBLT Oct2011 small

 

 

 

 

 

 

 

 

 

Construction notes

 

BLT - Lenz's Law

In the Spring of 2012, we presented a "Lenz's Law" demonstration.  In this demonstration, a cylindrical magnet is dropped down a vertical copper pipe and a vertical plastic pipe of identical lengths.  The time of travel is much longer because of the Lenz's Law effect.

   Construction notes  Magnets (K&J Magnetics - D4X0-ND), copper pipe (McMaster-Carr 50475k22), acrylic pipe (McMaster-Carr 8532K13)  Cost per unit less than $20.

 

BLT - The Falling Slinky

In the Fall of 2012 we presented the "Falling Slinky" demonstration, in which a slinky is dangled from the top and students are asked to predict who it will fall.  In this case a response worksheet and a video were developed to help with the presentation, and data where collected to investigate how the requirement for a written prediction affected students' understanding.

Here's a nice resource: http://www.youtube.com/watch?v=mAA613hqqZ0

BLT - Faraday's Jump Rope

 In the Spring of 2013 we presented the "Faraday's Jump Rope" demonstration.  25-foot length of six-conductor wire was configured into a loop with six turns.  The two ends of the loop were attached to a micro-amp galvanometer. 

construction notes

vendorpart 
Leads - alligator to bananaOmnimodels HCAP0108$3.99
GalvanometerWards16V 0537$16.50
Terminal BlockMcMaster Carr7527K46$2.76

terminal block wiring

Thermostat Cable (6-lead)McMaster Carr70985k75$11.50 ($0.23 per foot)
Unit price$34.75

BLT - Gauss Accelerator

The Gauss Accelerator is the BLT for the Fall 2013 semester.  This demonstrates the surprising results of the conservation of energy and momentum for collisions between a metal ball bearing (BB) and a powerful magnet.  Each unit consists of:

aone 32" long v-channel (McMaster Carr, 8982K541) resting on wooden blocks  $2.29 each

one Gauss Rifle kit (http://www.scitoyscatalog.com/mm5/merchant.mvc?Screen=PROD&Store_Code=SC&Product_Code=GAUSSRIFLE&Category_Code=M, $31.54 each)

Some electrical tape to secure the magnets to the v-channel at the positions 4 inches, 12 inches, 20 inches, and 28 inches.

BLT - Poisson Dot

The Poisson Dot BLT was presented in Spring 2014.  This demonstration is based on a historical event that illustrated the wave nature of light.  A green laser pointer (www.newegg.com $13.95 for tw0) was mounted so that the momentary contact switch was pressed on by a clothspin, which also mounted held the laser pointer in place.  A lens (http://www.mscdirect.com, #56451081 $10.35 each) was mounted into a rubber stopper with a #7 hole, mounted on the front of the laser pointer to expand the beam.  A standard BB ball bearing was glued to a microscope slide and also held with a clothspin on a table a distance away, where the diameter of the laser beam was slightly larger than that of the BB.  The poisson dot pattern appears on a distant wall.  For fun, we had the students read a SCRIPT describing this phenomenon.

Poisson DotDSC 0984small

Poisson DotDSC 0987small

     

BLT - Tension in a Pendulum

This is the Fall 2014 BLT.  A Spring balance (http://www.testequipmentdepot.com/ohaus/mechanical-balances/dial-spring/8014-mn.htm, $26 Each)