Linear Expansion LabIt doesn’t get much simpler than this. Measure the length of a metal rod at room temperature, and again at steam temperature. Calculate α. Bam!

It’s up to you to figure out the necessary math. But here are the deliverables (apart from the usual stuff) that will need to be in the report:

• The coefficients of linear expansion (including raw measurements) for four metals along with percent errors relative to known values

• A thorough examination of the strengths and weaknesses of the methodology including least precise measurement, least accurate measurement, and systematic errors that would account for deviations from known values. “Human error” won’t cut it!

Linear Expansion LabEQUIPMENT:

• Expansion apparatus including #2 rubber stopper with hole, large and small cork stoppers with holes

• Hotplate, boiler and rubber hose (gas hose for Bunsen)

• Goggles & tongs

• Meter stick, 100 ml beaker for condensate

• Computer, data logger and temperature sensor

ASSEMBLY: Put small cork on end of rod. Insert into jacket so cork is at lever end. Insert large cork at opposite end. Put jacket into stand. Lightly tighten holding screw. Adjust lever zeroing screw.

Linear Expansion LabHere’s enough info to get you started with the equipment:

Port for rubber stopper and Logger Pro thermometer

Outlet port to collect steam and condensate.

Inlet port for steam, generated using a boiler on a hotplate (not pictured).

Lever-arm contact point.

10:1 lever-arm indicating ΔL. 1 cm on scale = 1 mm ΔL.

Lever-arm L0 adjustment.

Linear Expansion LabPROCEDURE HINTS:

• STUFF WILL BE HOT! BE CAREFUL! USE TONGS! WEAR GOGGLES!

• It will take about 15 minutes for a half tank of water to first boil. Start the heating, then do other set up tasks.

• The ceramic tops on the hot plates retain heat for a LONG time. BE CAREFUL!

• Bring water to boil at “10”, hold at boiling at “7”.

• Set data collection to 1000 sec @ 1 sample per sec.

• At end of trial, drain water from jacket by tilting jacket before it’s removed from stand.