HP 5528A - Page 356

Mode l SS28A
Glo ss ary
GLOSSARY
Ambient: In the vicinity of; surrounding on all sides.
Ar csec, Ar cs cconds (with or without hy ph en): Your Angular measurements are displayed in
units of ";:I r e-sec ond s" ("ARC-SEC"). regardl ess of the se lling of the Measurement Displ ay 's rcar-
panel "English/
Metri c" switc h.
" Arcseconds" is a short way of saying "s econds of arc" . O ne ar cs econd equals 1/ 3600 of one
degree of arc.
Another way to visualize an ar csec ond is that ill s equivalcrH to 0. 000005 mm ( or inche s) for every
mm (
or inch) from your measurement ax i s. (This is the sa mc as 0 .5 mm in 1OOmetres,or about 0.3
inch in one mile .)
ASME : American Society of Mechanical Engineers
Coefficients of Th ermal hpan sion:
Material le ngth varies with te mp erature per
the
following expans ion coe fficient s:
Malerl al ppm l" C
Aluminum 23.1
Bra ss
19.4
St ee l
11 .7
Granite 11.0
Cast Iron 10.5
Pyrex Glass 3.2
INVAA
1.2-2.0
"Standard" material temperature is 20° C { Ga o Fl.
Conversion Factor s:
To Obtain Multiply
By
Mils Mi cro ns 0.039370
Inches Millimetres
0.039370
Feet Metres
3.280839
Microns Mils 25.4
Millimetr es Inches
25.'
Metr es Feel 0. 3048
' F - 9/ SI 'C i +32
'C - S/ 91 1' F i- 321
ppm l" F
12.8
10.8
6.5
6.1
5.7
1.8
0 .7 -1 .1
G-1