I have a buddy that is an engineer. Sometimes when we are in conversation he will pull some assumption out of thin air that he has calculated. I have challenged his claims, but lack the cranial capacity to put up good arguments against his theories. So I am looking for help. Please give me some good arguments against these claims:
A piece of Hardwood firewood costs 50 cents.
It costs 2.5 cents a minute to run hot water. 5 cents for cold. (At his house. He admits variables.)
A 50 yard punt with a hang time of 4 seconds travels at 30 MPH.
The optimal angle to shoot a free throw is 55 degrees.
A gas driven car is only 20% efficient at it's peak. In town only 7%.
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On the Fire wood thing
1 Cord of fire wood = 128 cubic ft
128 cubic ft = 221184 cubic in
for this discussion we use a piece of firewood 8"x8"x16" or 1024 cubic in. with those figures and the prices listed in todays paper for cords of Oak ($250)and Madrone
($325) there are 216 pieces of wood per cord costing for Oak $1.16each, and Madrone $1.50 each.
also the same cord of firewood cut to 6"x6"x12" would cost for Oak $0.48 per piece and $0.63 for Madrone
Those pesky variables
Truly worthless information. What a blog.
I find that this is very interesting.
Now all we have to do is find the cost wholesale. The cost of production and how to make a living that pays 27 dollars and hour, and employ 300 people.
As far as the others... the hot water thing, for his house, he's probably right, but to many variables for it to right for every home. (size of water heater, water heater temp. setting, etc.)
The punt... didn't figure it out, but a simple time, distance, speed so it's more than likely correct.
The free throw... a whole different ball of wax there. 55 degrees works only with the proper amount of applied force. To much force and you over shoot, not enough force and it's an air ball. So if 55 degrees is the optimum angle based on ball size and rim size one must calculate in the proper force or the 55 degrees is moot.
If you "do the math", 30mph is 44 feet/second.
Theortically, a ball kicked at that speed for best distance would fall to the ground in only 18 yards and 1.75 seconds.
To make a theoretical 50 yard punt, the ball has to be kicked 48 mph for best distance and would hang for about 3 seconds.
Real footballs don't go as far because of air drag. 50 yard punts are kicked about 59 mph and hang for almost 4 seconds.
Keep those arguments coming and I will let my buddy Ron refute! May have to done over a beer at Big Louies!
The gas engine efficiency is about 20%, fuel to car wheel efficiency is about 15%.
http://courses.washington.edu/me341/oct22v2.htm
But if you count only energy needed to move a person from one place to another as what you get out, the efficiency of a gas car is much lower.
Based on the the energy needed to move a 210 lb Richard Marks around, the highway gasoline efficiency is more like 1.5%. Having more passengers would increase the efficiency.
If you add in the energy used to produce and deliver the petroleum, manufacture and maintain the car, and build and maintain the roadway, the efficiency would be lower, around 0.5%.
Ron owes you a beer. Here's a reference for measurements of actual punts:
http://www.docstoc.com/docs/5331439/football-and-physics
On the punt
50 yds = 150 ft
1mph = 1.466fps
So a football traveling 150 ft in 4sec has a speed of 37.5 fps which figures to 25.58 mph
150ft/4sec = 37.5fps
37.5fps/1.466mph = 25.58mph
" Anonymous said...
Truly worthless information. What a blog.
3:04 PM"
kind of like anonymous comments
If I were you I would just tell my friend that you are glad someone is keeping up with the trivia and you know who to call if you are ever on Millionaire.
I am not sure mathamatic solutions would be called trivia. Maybe a spot on smarter than a fith grader, but not trivia. Course you may not make the greade to comprehend that.
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