measurement systems and tools and their role in technology objectives define measurement compare the...

Measurement Systems Measurement Systems and Tools and Their Role and Tools and Their Role in Technologyin Technology

Objectives•Define measurement•Compare the U.S. customary and the metric measurement system.•Describe the major physical qualities that can be measured. •Name types of measurements.•Identify common measuring tools to measure linear distances, diameters and angles.•Relate measurement to quality control.

LANCE TATRO CHSE 2010

Measurement Systems: Measurement Systems: Past and PresentPast and Present

Measurement: Comparing the quality being described against a standard.

In early times, people used parts of the body for measurement.

U.S. Customary: Based on a system developed in England somewhere between the 1100s to 1500s. (Inch means thumb width, and foot was based on the length of the human foot.)

SI Metric System: Developed in the 1790s by a group of French Scientist. Based on units of 10. Smaller units are in 1/10, 1/100, and 1/1000 and larger units are multiples of 10, 100, and 1000.


The bases for early units of The bases for early units of measurementmeasurement


Comparing Comparing U.S. to SIU.S. to SI


Qualities MeasuredQualities MeasuredSize and Space:

The length, area or volume of an object.

Mass: The amount of matter in an object.

Temperature: How hot or cold an object is.

Time: How long an event last.


Size and SpaceSize and Space3 Different encounters: Length, Area, and

Volume.Length: Distance between two points.Many parts are described as having

Depth, Width and Height. Finished products are typically

described in height, width and depth.Common Units (U.S. Customary): Inch, foot,

yard, and mile. I mile = 5280 feet


AreaAreaLength and Width multiplied

If the length of the page is 11 inches, and the width is 8, the total area covered by the page is 88 square inches.

8”

11”

88 square inches


VolumeVolumeVolume is the amount of space

an object occupies. Finding volume: Multiply the

Length X Width X Depth

Width

Dep

th

Lengt

h


MassMassMass is the quantity of matter present

in an object. Mass is not the same thing as weight.

Although there is a relationship, weight is the force of the gravitational pull on a mass.

We use Mass and Weight interchangeably because “On Earth”, the mass is very close the gravitational pull, and it remains constant everywhere on earth.

Units of weight is U.S. customary are ounces and pounds and in SI they are in terms of grams.


TemperatureTemperatureTemperature is the measurement of

how hot or cold something is. The term “Hot” and “Cold” are

relative and must be compared to something else.

Cold refers to the “Absence of heat”Fahrenheit scale has 180 degrees

between freezing and boiling points. Range is from 32-212

Celsius scale has 100 degrees, whereas the range is between 0-100


TimeTimeTime refers to how long an event

lasts.Units of measurement are universal

between U.S. and Metric.SecondsMinutes (60 seconds)Hour (60 minutes or 3600 seconds)Year (1 year = 8 765.81277 hours)


If a car is traveling 60 MPH, If a car is traveling 60 MPH, how many feet is it traveling how many feet is it traveling per second?per second?1 mile is 5280 feet@ 60mph the car is traveling 5280 X 60Or 316800 feet.1 hour = 60 minutes, or 3600 seconds316800/3600 Answer: 88 feet/secondCan you calculate the Yards per second?29.33Yds/second


Types of MeasurementTypes of MeasurementStandard Measurement: If a

product is acceptable to be within fractions of an inch, and not required to be extremely precise.

Precision Measurement: Where Standard Measurement is not accurate enough, and are required to be within 1/1000th or 1/10000th

Example: A piston in a motor would be deemed useless if it had a variance of1/32.


Measurement Tools Measurement Tools Direct Reading Measurement

Tools

Three common uses of measurements are finding linear dimensions, diameter measurements and angle measurements.


Linear Devices Linear Devices Most common is the Rule


Measuring….Measuring….

72 mm

2 1/8


Comparing RulesComparing Rules

Breaking down a fractional Breaking down a fractional RuleRuleLongest lines are inch markers2nd longest lines are ½ inch markers3rd longest are ¼ inch markers4th longest are 1/8 inch markers


Machinist’s Tools Machinist’s Tools Micrometer Vernier Calipers Depth Gauges


Angle Measuring DevicesAngle Measuring DevicesAngles between 90 edges are

commonly done with squares.45 degree angles are measured

using carpenter’s square or a try square.


Checking for square…Checking for square…

Is this page square on the presentation?


Remember…Remember…When we are measuring

something that does not require a great deal of precision, we can use a common ruler.

For any greater precision, we need to use tools that allows use to measure 1/1000th of an inch.


measurement systems and tools and their role in technology objectives define measurement compare the...

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