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Full Question:

Paper is made from wood pulp. Estimate the number of trees that must be cut down to make one day's run of a big city's daily newspaper. Assume no recycling.

2007-09-06 09:54:04 · 1 answers · asked by Anonymous in Science & Mathematics Physics

1 answers

http://www.fs.fed.us/pnw/pubs/pnw_rp374.pdf
"
2. A standard cord of wood is 128 cubic feet
3. A tree with a usable height of 40 feet and a circumference of 75 inches
will contain about one cord of wood.
4. Douglas Fir has an average density of 28 pounds per cubic feet (I assume
this is wet weight)
5. Dry weight is about 50% of wet weight


Rougly speaking, a cord of wood based on the above assumptions would weigh
about 3600 pounds and assuming 40% yield, would produce about 720 pounds of
paper. 720 lbs is about 327 kg per tree."


On weekdays the Sf Chronicle circulates just under 1 million copies.
For estimation, let's use 1 million
The average weight of an issue is 1 kg
so one day uses 1 million kg of paper

divide 1 million by 327

over 3,000 trees per day

The Chronicle does use 27 lb paper versus 32 lb by the NY Times and SJ Merc.
Also, the Chronice uses 53% recycled material.
Still, that's almost 1500 trees per day

yikes!

j

2007-09-06 10:56:33 · answer #1 · answered by odu83 7 · 0 0

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