Can someone explain paper density to me please? Like how can 500 sheets of letter size paper be "20lbs"?

Answer 1

For "bond" paper the standard paper size is 17" x 22". The "weight" is the weight of 500 sheets of the standard size.

Answer 2

The weight of a sheet is 500 pieces in the "basis sheet size", which is usually 8 to 12 finished sheets. Thus, a ream of letter size paper of a certain weight is lighter than a ream of the same paper in legal size or tabloid.

However, even the size of the basis sheets varies from manufacturer to manufacturer and from paper brand to another.

I don't actually pay too much attention to the basis weight except as a rough guide. More important is the type — bond, writing and cover are the usual ones, in increasing order of heaviness — and the feel of actual paper swatches.

Answer 3

Basically it is a measure used in America to diffentiate the thickness and weight of a ream of same sized paper. For example, a 500 sheet ream of 20 pound paper is lighter and thinner than a 500 sheet ream of 32 pound paper.

This is accomplished by using the same sheet size (called basis size) for the same type of paper, allowing consumers to easily compare papers of differing brands. Thus 20 pound bond letter size and 20 pound bond legal size papers are the same weight paper having even though they are of a different size.

Answer 4

x number of pounds for a paper means that if say 20 pounds of weight was attached to the bottom a sheet of paper with a clip the paper would not tear apart until after the weight that is stated is reached. so a 20 pound sheet would hold 20 pounds then tear . this is a method of letting the people know how thick and tough the paper is .
i can tell you that a box full of papers can be very heavy. i work now as a mover and before as a printer.

Answer 5

in general for ordinary matter, not anti-matter,
the density is mass/volume for measurable
chucks of matter or dm/dV as a calculus
formula for continuous distributions of matter.

And, for something as ordinary as a ream of paper,
you can calculate the density as
scale weight/(length x width x height).

So you can see that the density is going to
change depending on how tightly the
sheets of paper are packed together,
although the 20lb scale weight stays
the same, no matter how they're packed.
And that's because the trees and water from which
the paper is made, has a fixed density.

Answer 6

20 pounds is the weight of 500 sheets ( a ream) of the paper in full sized sheets, which we almost never see. (Take a look at folio, quarto, octavio terms which are foldings of the full sheet.)
http://www-tcad.stanford.edu/~goojs/REFERENCES/paper_standard.html

Answer 7

Dear Ryan,

I do not want to give u big lecture.

U may take PAPER Density as

1.32665 grms/cm sq. approx.