Ch 3 - Measurement Flashcards
meter (m) measures the dimension of
length
kilogram (kg) measures the dimension of
mass
second (s) measures the dimension of
time
ampere (A) measures the dimension of
electric current
kelvin (K) measures the dimention of
absolute temperature
mole (mol) measures the dimension of
the amount of a substance
candela (cd) measures the dimension of
radiant intensity
peta (P-) means quadrillion which is exponent form:
10 to the 15th power
tera (T-) means trillion which is exponent form:
10 to the 12th power
giga (G-) means billion which is exponent form:
10 to the 9th power
mega (M-) means million which is exponent form:
10 to the 6th power
kilo (kill-o) (k-) means thousand which is exponent form:
10 to the 3rd power
hect- / hecto- (h-) means hundred which is exponent form:
10 to the 2nd power
deka (da-) means ten which is exponent form:
10 to the 1st power
1 is the base for metric and is in exponent form:
10 to the zero power
deci- (d-) means tenth and the exponent form is
10 to the negative 1 power
centi- (c-) means hundredth and the exponent form is
10 to the negative 2 power
milli- (m-) means thousandth and the exponent form is
10 to the negative 3 power
micro- (mu) means millionth and the exponent form is
10 to the negative 6th power
nano- (n-) means billionth and the exponent form is
10 to the negative 9th power
pico- (p-) means trillionth and the exponent form is
10 to the negative 12th power
If your data doesn’t match predictions, what 4 things could be wrong:
You may have: used instrument wrong, read instrument wrong, instrument is broken/damaged, or the environment wasn't good for measuring.
Definition of accuracy
assessment of the measurement error.
AKA Indicates how close a measurement is to its acceptable value (smaller error means more accurate measurement).
Definition of precision
assessment of the exactness of a measurement (more precise = more known digits). [Tool with finer markings can measure more precisely.]
Definition of unit
a value of 1 (for any portion of a dimension).
Measured data shows two things:
a number and a dimensional unit.
France standardized measurements first, by establishing the decimal metric system.
True
Number of base units the SI system has:
7 (m,kg,s,A,K,mol,cd)
Precision does not apply to two things:
exact counts and quantities that are defined. (Precision applies to measurements, not counts or definitions.)
Measurements can end with a zero that is significant in which case?
When a decimal point is present (all zeros to the right of the last nonzero digit are significant)
T/F? Every measurement contains error, no matter how good the instrument and the observer are.
True
weight indicates the amount of matter in an object, but it does not measure the amount of matter directly.
True
Weight is the force of earth’s gravity acting on the matter of an object. T/F?
True
Gravity on earth’s surface changes depending on various factors. T/F?
True
Examples of quantitative data (numerical measurements):
temp, speed, time, volume
Examples of qualitative data (word descriptions)
audibility of sound, pattern, shape, color
T/F: Actual value of a measurement is more correctly referred to as “acceptable value” (because nothing can be perfectly measured enough to give us it’s ‘ACTUAL value’)
True
Mass is a constant for a given object (it doesn’t depend on gravity).
True.
Weight depends on the pull of gravity
True.
What do we call the space occupied by an object?
it’s volume.
Density is the amount of matter (mass) contained in an object compared to its volume.
True (D=M/V)
Abbreviation for the system of internationally accepted metric units:
SI
measurement error tends to be reduced by averaging several measurements of the same object
True
The difference between each measurement and the average of many measurements is called random error.
True
