Page 39 - Appplied Mathematics for the Petroleum and Other Industries, 5th Edition

GLOSSARY 299

inertia n: the tendency of a stationary object to remain lowest common denominator (LCD) n: the smallest
stationary or of a moving object to continue moving in number that all the denominators in a series of fractions
a straight line, unless acted upon by an outside force. will divide into evenly.
interpolate v: to insert or estimate values between two
known values.
mass n: the quantity of matter a substance contains,
independent of such external conditions as the buoyancy
joule (J) n: the unit of work and energy in the SI system, of the atmosphere or the acceleration caused by gravity.
also known as the newton-metre (N•m).
mean n: the average of two or more observed values.

Kelvin scale n: the absolute temperature scale for met- means n: the second and third terms of a proportion.
ric measurements, in which 0 indicates absolute zero measured depth (MD) n: the total length of the well-
temperature. bore, measured in feet along its actual course through

kick n: an entry of water, gas, oil, or other formation the Earth. Measured depth can differ from true vertical
fluid into the wellbore during drilling, workover, or other depth, especially in directionally drilled wellbores. See
operations. It occurs because the pressure exerted by the true vertical depth.
column of drilling or other fluid in the wellbore is not median n: a statistical measure of the midmost value,
great enough to overcome the pressure exerted by the such that half the values in a set are greater and half are
fluids in a formation exposed to the wellbore. If prompt less than the median.
action is not taken to control the kick, or kill the well, a
blowout may occur. See blowout. metre n: the SI base unit of distance equal to 100 cen-
timetres or about 3.28 feet.
kilogram n: the metric unit of mass equal to 1,000 grams.
mile n: a conventional unit of distance equal to 5,280 feet
2
kilograms per square centimeter (kg/cm ) n: a measure or 1,760 yards and approximately 1,609 metres.
of pressure that falls outside the definition of force per
unit area but may still be encountered where people minuend n: the number from which another number is
employ the old metric system rather than using SI units. to be subtracted.
2
One kg/cm is equal to about 98 kPA or 14.2 psi. mode n: the value that occurs most frequently in a set
kilowatt (kW) n: a metric unit of power equal to ap- of data.
proximately 1.34 horsepower; 1,000 watts. See watt.
multiplicand n: the number that is to be multiplied or
increased in multiples.
leap year n: a year occurring every four years that contains multiplier n: the number of times that the multiplicand
366 days by adding a 29th day to February in order to is added to itself.
keep synchronized with the astronomical or seasonal year.

light year n: a measure of distance indicating the distance
that light would travel in one year, equivalent to 9.4607 natural logarithm n: a logarithm to the base of e, which
12
× 10 km or 5.88 trillion miles. equals approximately 2.718. This type of logarithm
line graph n: a type of graph in which data is represented comes about naturally in a mathematical process.
by points connected by one or more lines to show trends Newton per square metre (N/m ) n: the SI unit of pres-
2
and patterns in the data. sure, also known as a pascal (Pa).
liquid measure n: a unit or series of units for measuring number key n: a key on a computer or calculator that
Petroleum Extension-The University of Texas at Austin
the volume of liquids. allows the user to enter a numeral into the display.
log abbr: logarithm. numerator n: in a mathematical fraction, the number or
logarithm n: the exponent that indicates the power to term that is written above the line and is to be divided
which a number is raised to produce a given number. by the denominator.
For example, the logarithm of 100 to the base 10 is 2.
lower range value (LRV) n: the lowest value of the
process variable to be measured and calibrated. oblique triangle n: any triangle without right angles.