Physical quantities can be measured in different units. For example, length can be measured in meter or inch (or many other units). Thus the unit is an integral part to your answer. The numerical value of an answer will be different for different units.
Some CAPA problems ask you to enter your answer in a specific unit, in this case a numerical value for an answer is enough. Some problems do not specify the units and you need to enter the unit you have chosen as part of your answer.
The CAPA system will first check the unit of your answer, then the number of significant digits, and then the numerical value. The CAPA system will inform you if either the units or the number of significant digits in your answer are incorrect. Incorrect units or number of significant digits will not count against your maximum number of tries.
Here is an example how you can enter units into the CAPA system:
16.7 Joules per meter squared can be entered as
1.67E1 J/m^2OR
1.67E1 J*m^-2OR
16.7 J/m^2OR
1.67E-3 J/cm^2OR ....
Note the format:
The following table lists all units the CAPA
system accepts and the symbols you want to use to enter them into
CAPA:
Base units
name symbol quantity
-------------------------------
meter m length
kilogram kg mass
second s time
ampere A electric current
kelvin K thermodynamic temperature
mole mol amount of substance
candela cd luminous intensity
Prefix symbol factor
----------------------------------
yotta Y 10^{24}
zetta Z 10^{21}
exa E 10^{18}
peta P 10^{15}
tera T 10^{12}
giga G 10^9
mega M 10^6
kilo k 10^3
hecto h 10^2
deci d 10^-1
centi c 10^-2
milli m 10^-3
micro u 10^-6
nano n 10^-9
pico p 10^{-12}
femto f 10^{-15}
atto a 10^{-18}
zepto z 10^{-21}
yocto y 10^{-24}
Derived units
name symbol conversion quantity
-----------------------------------------------
gram g 0.001 kg mass
pound lb 0.45359237 kg mass
ounce oz 1.77185E-3 kg mass
hour hr 3600. s time
inch in 2.54 cm length
foot ft 12 in length
mile mi 5280 ft length
yard yd 0.9144 m length
nautical_mile n_mi 6080 ft length, nautical mile (UK)
astroUnit AU 1.4959787E11 m length mean earth-sun distance
rood rood 1210 yd^2 area, rood
acre acre 4840 yd^2 area, acre
hertz Hz 1/s frequency
litre L 10^3/cm^3 volume
newton N m*kg/s^2 force
pound_force lbf 4.44822 N force
dyne dyn 1E-5 N force
pascal Pa N/m^2 pressure, stress
bar bar 1E5 Pa pressure
mmHg mmHg 1.33322E2 Pa pressure, millimeter of mercury
torr torr 1 mmHg pressure
atm atm 760 torr standard atmosphere
joule J N*m energy, work, heat
electronvolt eV 1.6021892E-19 J energy
calorie cal 4.1868 J energy
Btu Btu 1.05506E3 J energy
watt W J/s power, radiant flux
coulomb C A*s electric charge
volt V J/C electric potential, electromotive force
ohm Ohm V/A electric resistance
siemens S 1/Ohm electric conductance
farad F C/V electric capacitance
tesla T V s/m^2 magnetic flux density
weber Wb V*s magnetic flux
henry H V*s/A inductance
radian rad m /m plane angle
degree deg 1.745329E-2 rad plane angle (Pi rad=180 deg)
steradian sr m^2 /m^2 solid angle
lumen lm cd*sr luminous flux
lux lx cd*sr/m^2 illuminance
becquerel Bq 1/s activity (radioactive)
gray Gy J/kg absorbed dose (of radiation)
sievert Sv J/kg dose equivalent (dose equivalent index)
This document http://www.pa.msu.edu/courses/1997fall/PHY231/capa_units.html was last updated on 20 August 1997 by Thomas Glasmacher.