Download - Measuring presentation 2014
Nature of
ScienceMeasurement & Metrics
The International System
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The Basics – SI (International System formally known as the Metric System)
International System of Units (SI)
International system, accepted world-wide
Based on units of 10
Four basics types of measurementDistanceMassVolumeTemperature
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Prefixes & Amounts Slide
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Units for Measuring Distance(length)
Base unit is a meter
Abbreviation = M
1,000m = kilometer
0.01m = centimeter
0.001m = millimeter
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A military slang, a "klick," is equal to a distance of 1,000 meters, or 1 kilometer, or ø.62 miles).
100 klicks south is a solder’s way of saying 100 kilometers away, or 62 miles away.
Believed to come into the language during the Vietnam War.
Officially
The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second.
Distance Factoid: “Klick”
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Units for Measuring Mass
Base word is gram
Base unit is kilogram
Abbreviation = g
1,000g = kilograms
0.001g = milligrams
Note: •Despite the prefix “kilo-”, the kilogram is the base unit of mass. •The kilogram, not the gram, is used in the definitions of derived units.•Nonetheless, units of mass are named as if the gram were the base unit.
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Gravity
Mass is the amount of matter in an object.
Weight is not the same as mass.
Weight is the force of gravity pulling on an object.
Weight varies with the mass of the object and the strength of gravity.
Objects weigh more at sea level, which is nearer the center of the Earth, than up a mountain.
A person on the Moon weighs one sixth of their weight on Earth.
Mass Factoid:
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Units for Measuring VolumeBase unit is a liter
Abbreviation = L
1,000L = kiloliter
0.02L = centiliter
0.001mL = milliliter
Also: cubic centimeter = cc or cm3
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The Meniscus
A liquid surface is curved.
A relatively strong attractive force between water and glass.
The curved surface is called the meniscus.
Measure from the bottom of the meniscus.
Volume Factoid:
Meniscus
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Volume of an Irregular Solid• Pour a set amount of water into a graduated cylinder or
beaker, example 100 ml.
• Place irregular shaped object into vessel.
• Measure difference between original meniscus line and new meniscus line.
WaterDisplacement
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Units for Measuring Temperature
Degrees are in Celsius
Abbreviation = °C
Know these temperatures100°C = boiling waterØ.37°C = body temp.Ø.20°C = room temp.Ø.0°C = freezing water
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-273.15°C Absolute zero is the lowest
possible temperature where nothing could be colder and no heat energy remains in a substance.
Absolute zero is the point at which the fundamental particles of nature have minimal vibrational motion, retaining only quantum mechanical, zero-point energy-induced particle motion.
By international agreement, absolute zero is defined as precisely; Ø °K on the Kelvin scale, which is a thermodynamic (absolute) temperature scale; and –273.15 °C on the Celsius scale.
Absolute ZeroTemperature Factoid:
http://www.sciencedaily.com/articles/a/absolute_zero.htm
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