Transcript

Objective 4.01AMeasurement

SystemsUS Customary

System

Measurement is

the process of determining the size, amount or extent of something. It objectively

describes the physical qualities of an object.

It is also the practice of comparing qualities of an

object to a standard.

There are 2 types of measurement:

1. Standard measurement• Do not require close

measurement

2. Precision measurement• Requires close measurements

Standard Measurement:

Standard measurement is widely used in the construction

industry.

PrecisionMeasurement:

Precision measurement is widely used in the manufacturing

industry.

The two measurement systems:

•US Customary System

•SI Metric System

The U.S. Customary system uses

unique units for each quality being

measured. The lack of uniform

multiples can make the system

confusing. It is based on units of

measurement established during the

Middle Ages in Europe.

U. S. Customary system basic units of measurement• Length is the inch

• Weight is the pound

• Area is square feet

• Volume is the quart

• Temperature is degrees Fahrenheit

• Energy is BTU

• Power is horsepower and watts

U.S. Customary

measurement for Length12 inches = 1 foot

3 feet = 1 yard

1,760 yards = 1 mile

5,280 feet = 1 mile

U. S. Customary measurement for Weight

16 ounces = 1 pound

2,000 pounds = 1 ton

U.S. Customary

measurement for Volume 8 ounces = 1 cup

2 cups = 1 pint (16 ounces)

2 pints = 1 quart (32 ounces)

4 quarts = 1 gallon (128 ounces)

Note!!!!!!!

Ounces (oz.) are used in

both weight and volume

U. S. Customary measurement for Temperature: Fahrenheit (0F)

freezing point of water = 320F

boiling point of water = 2120F

1800F between boiling/freezing

The appropriate term for the absolute temperature

scale is Rankine

Objective 4.01BSI Metric System

The metric system was established in France.

Metric Prefixes

“There is a logical progression from smaller units to larger ones, since all sizes of units

are based on ten.”

(R3 p.119) Technology Systems

The Base Units of the Metric system are:

• Length = meter

• Weight = gram

• Volume = liter

• Temperature = degrees Celsius (0C)

• Energy = Joules and calories

The metric system uses the same

prefixes for all base units.

kilo = x 1000

hecto = x 100

deka = x 10

deci = x .1

centi = x .01

milli = x .001

Metric Length

Base unit is the meter

1000 millimeters = 1 meter

100 centimeters = 1 meter

1 kilometer = 1000 meters

Metric Volume

Base unit is the cubic meter or liter

1000 cubic centimeters = 1 liter

1000 milliliter = 1 liter

Metric Weight

Base unit is the gram

1 kilogram = 1000 grams

1 metric ton = 1000 kilograms

Temperature: Celsius (0C)

freezing point of water = 00C

boiling point of water = 1000C

1000C between boiling/freezing

Objective 4.01C Measurement

Tools

Three common uses of measurement are finding:

1. linear dimensions

2. diameters

3. angles

Each of these three features can be measured using standard or precision devices.

Linear Measurement

• The most common measurement device is the rule (1/16 in. and mm).

• You can also use a tape.

• Precision measurement is done with vernier calipers.

Rules are used to measure length, width, and thickness. The rule is the most common linear measurement device.

• standard 12 inch rule

• mechanical rule/scale

• drafter’s rule/scale

• architect rule/scale

• machinist’s rule/scale

• metric rule

• yard stick

• meter stick

• tape measure

Measuring diameter

• Measuring round material or parts.

• Rough measurement is done with hole gages or circle templates.

• Precision measurement is done with a micrometer.

Calipers

Calipers are used to measure

diameters and length on either the

inside or outside of an object.

Micrometer• Micrometers are used to measure

the length, thickness or diameter

of small objects in very precise

increments, thousandths (0.001)

of an inch.

Measuring angles

• Measurement of 900 angles are done with squares.

• Protractors may also be used for angles that a square will not measure

Squares Squares are used to measure or lay out Perpendicular Lines (lines at 90 degree angles).

• T-Square• try square• framing square• combination square• center square

Protractors

• Protractors are used to measure angles from 0 to 180 degrees.

• Many protractors can also be used to measure length along their straight edge.

Weight Scales

• Common bathroom scales

• Most sensitive scientific scales

• analog/digital

• manual or electronic

Weight scales measure mass or weight

Calibrated Containers are used

to measure volume. • Cooks measure ingredients for

recipes

• Scientists use calibrated

containers to measure volume

• measuring spoons, measuring

cups, and lab breakers are

calibrated containers

Types of Measurement Tools

1. Direct –reading measurement tools

2. Indirect-reading measurement tools

Direct Reading measurement tools

Measurement tools that an operator manipulates and reads.

Indirect Reading Measurement tools

Example:

Sensors gathering measurements and then displaying them on an output

device.

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