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Flashcards in Test 3 Deck (26):
1

A_is the act of comparing and unknown quantity to a standard unit. Consists of a_and a_

Measurement, number, unit

2

An_is any artificial device made for the purpose of refining, extending, or substituting for the human senses when measuring

Instrument

3

A__system is any measuring system in which different sized units are related to each other by multiples of 10

Metric

4

Area

Square meter

m^2

5

Volume

Cubic meter

m^3

6

Mass density

Kilogram per cubic meter

kg/m^3

7

Metric ton

Mass

t

8

Atomic mass unit

Mass

u

9

A__is a fraction that contains both the original unit and it's equivalent value in a new unit and is_to_

Conversion factor, equal, 1

10

What is the basic rule for using conversion factors

In a conversion factor ratio, the new unit is in the numerator and the old unit is in the denominator

11

A quantitive term that describes how close a measurement is to the actual or accepted value of the dimension being measured

Accuracy

12

What is the formula for percent error

(|o-A|/A)•100%

O= observed value

A= accepted value

13

If the percent error is_, then the measurement is considered to be accurate

Small

14

A quantitive evaluation of the exactness of a measurement or a measuring instrument

Precision

15

While accuracy indicates how__a measurement is to the actual value, precision indicates how__and measurement is or how_one can make a measurement

Close, repeatable, exactly

16

What three purposes do significant digits serve

1- they determine the important digits you need to record when making a measurement

2- they indicate the precision of your measurement

3- it helps scientists to report measurements honestly

17

The__of a measurement consists of all the certain digits +1 estimated digit

Significant digits

18

When using significant digits the estimated digit is given in?

Tenths of the smallest subdivision on the instruments scale

19

Rules for adding and subtracting measure data

1- Measure data must be the same kind of dimension and have the same units before they can be added or subtracted

2- The sum or difference of measured data cannot have greater precision than the least precise quantity in the sum or difference

3-The product or quotient of measured data cannot have more significant digits in the quantity with the fewest significant digits

4- The product or quotient of a measurement and a counted number, conversion factor, or defined value has the same number of decimal places, or same precision, I see original measurement

5- in compound calculations, do not round off at the intermediate steps

20

**** five steps in problem-solving****

1- read the problem

2- determine the method of solution

3- choose the specific tools to use

4- set up the problem, estimate, and calculate

5- check and format

21

+

-

Least precise

22



/

Least significant figure

23



/

With counted number

Go to the decimal place

24

Density equals

D=m/v

25

Volume equals

v=m/D

26

Volume units are always

Cubic length measures