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Meter v. foot

Meter - Originally one ten-millionth (1/10,000,000) of the distance from the Earth's equator to the North Pole (at sea level), its definition has been periodically refined to reflect growing knowledge of metrology. Since 1983, it is defined as the length of the path travelled by light in vacuum in ¹⁄_299,792,458 of a second.

Foot = 12 "thumbs," first "calibrated" as King Henry I's foot in 1068, but used since about 2500 BC

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Smoot

Oliver R. Smoot - a MIT fraternity pledge who in October 1958 lay on the Harvard Bridge (between Boston and Cambridge, Massachusetts), and was used by his fraternity brothers to measure the length of the bridge.

One smoot is equal to Oliver Smoot's height (five feet and seven inches ~1.70 m).

The bridge's length was measured to be 364.4 smoots (620.1 m) plus or minus one ear, with the "plus or minus" intended to express uncertainty of measurement.

To implement his use as a measuring unit, Oliver Smoot repeatedly lay down on the bridge, let his companions mark his new position in chalk or paint, and then got up again. Eventually, he tired from all this exercise and was carried thereafter by the fraternity brothers to each new position.

Oliver Smoot graduated from MIT with the class of 1962, became a lawyer, and later became chairman of the American National Standards Institute (ANSI) and president of the International Organization for Standardization (ISO).

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Create a unit

Objective

In this experiment, you and your group will be creating a unique unit of measurement based on the height of one of the members of your lab group. You will then figure out how to measure objects around the room and in the building using your new unit of measurement.

Background

Since you are designing your own measuring system, I ask that you follow a little of the world convention. The name of the unit of measurement will be the last name of the chosen student. So if the student is named Sabine Proehl, we will call the unit a “Proehl.” The length of one Proehl will be the student’s height. When you divide the Proehl into tenths, the new unit will be called deciproehls. Should you be smart enough to divide the unit into hundredths, those units will be called centiproehls.

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Materials

A student volunteer from your group
String
A meter stick
A marker
You may request additional material if you think it will be helpful

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Setup:

Break into groups of three. Chose a volunteer from your group to become the standard by which everything is measured.
Very carefully and accurately measure his or her height using a meter stick and record this data on the back of this handout.
Cut a piece of string to the length of your volunteer.
Figure out how to calibrate your string to tenths and hundreds of “units.”
Return the meter stick to the front of the room.

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Procedure:

Measure the length of the desk in your unit. You must measure the desk to at least three decimal places. In other words, your answer must be in the form 0.001 units and it must be accurate.
Measure the length of my classroom using your unit of measurement.
Measure the distance from the doors to the science wing to the doors to the outside.