Lab 2: Potatoes and Pendulums

You are visiting a local organic potato farm and are discussing the possibility of buying the farmer's potatoes to use in the COA dining hall. The farmer is very interested and asks you approximately how many pounds of potatoes COA would need each month. Come up with an order of magnitude estimate of the pounds of potatoes used in the dining hall each month. Do this problem without a calculator.
How much land would be needed to grow these potatoes? Consult the seed catalog. Apparently in Maine soil it is possible to get around 20 lbs of potatoes from one pound of seed.
How much would the seed cost? What is the approximate value of the crop?

Trigonometry Warm Up.

You stand 50 meters away from a flag pole. You have to look at an angle of 53 degrees from the horizon to see the top of the pole. What is the pole's height?
You stand 75 meters away from a tree that's 100 meters tall. At what angle must you tilt your head so that you look straight at the top of the tree?

Applied Trigonometry

Grab a sextant (or two). Go outside and figure out how to use it. (Read the manual and talk to me.)
Measure the height of the large pine tree on the North end of the field between the dorms and the arts and sciences building.

From P. Tipler, Physics for Scientists and Engineers, Third edition, Worth Publishers, 1991.

The period T of a simple pendulum depends on the length L of the pendulum and the strength of earth's gravitational field g. Find a simple combination of L and g that has the dimensions of time. The quantity g has dimension of length/time^2.
Check the dependence of the period T on the length L by measuring the period for three different values of L. (The period T is defined as the time for a complete to-and-fro swing.)
The correct formula involves a numerical factor that is dimensionless and hence can't be obtained by dimensional analysis. Using your data from the above question, estimate the value of the numerical factor.

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