Derive v = 3 L for the coefficient of thermal expansion of materials. When X=Y=Z and change
V = l03
V = V -V
l)3 - l 3
l =l 3 T
v = (3
l+3l l2+ l 3) - l 3
l )/( l T)
New York City
A photographs shows the messenger boy Ehrich Weiss
at the age of 13. He lived with his family at East 69 th street.
When he was 16, his father became ill and unable to work.
Then he and his brother had to work harder. He joined Pastime