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Terminal Velocity Investigating Forces and Motion in our Universe. Expedition 1 The Quest for Exactness. Objectives. To accomplish your expedition goal successfully, you will need to Evaluate systems and standards of measurement. Use measurements to describe objects in your environment.
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Terminal VelocityInvestigating Forces and Motion in our Universe Expedition 1 The Quest for Exactness
Objectives • To accomplish your expedition goal successfully, you will need to Evaluate systems and standards of measurement. • Use measurements to describe objects in your environment. • Discover why SI units are critical for communication among scientists, engineers, industrial partners, and societies. • Explore how measurements derived from SI units can be used to further describe your physical environment. • Compare accuracy and precision when analyzing measurement results. • Assess how technological advancements to measurement tools impact society.
A modelis any representation of an object or event used to explain the natural world.
When a scientist or engineer collects data, the information is generally first put into a datatable
Scientists use graphsto turn these raw numbers into a visual representation. Common graphs include line, bar, and circle graphs.
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Length– the distance between two points, • Time – the interval between two events
Mass – the amount of matterin an object • Temperature– the amount of energy within a sample of matter
Electric current – the flow of charges • Amount of a substance – the number of atoms or moleculesin a sample of material, and
Luminous intensity – the measure of lightintensity coming from a source. • Metrology is the study of measurement.
An estimate is an approximate measurement of an object or event
The Metric System • The MetricSystem is a base-ten system
SI units are the current world standard for measurement. There are seven basic SI units. They are the meter, kilogram , second, ampere, kelvin, mole and candela.
Each unit is used to measure a particularquantity • Additionally, SI units can be combined to describe area, volume, density, speed, and acceleration.
Scientific prefixes allow us to reduce the number of zeros and make the figures more manageable. For example, 54,500,000,000 meters = 54.5 giga-meters, and 400,000,000,000 meters = 400 gigameters
Converting Metric Units • When you are converting from a big unit (like kilometers) to a smaller unit (like millimeters), youmultiply. • When you are converting from a small unit (like millimeters) to a larger unit (like kilometers) you devide.
U.S.Customary Units- used in only 3 countries? • The U.S. ______________, and ___________
Derived units use more than one measurement at a time. Some examples include area, volume, density, speed, acceleration, and weight. • Areais the size of the surface of a two-dimensional object.
Your body displaces, or pushes out, an amount of water equal to the volume of your body below the water line.
Speed is the change in distance over time. • Accelleration is the rate of the change in velocity.
Weight is the force exerted on any object with mass by the gravitational acceleration of a body such as a planet.
Mass is the amount of matter in something. Matter is anything that has mass and takes up space.
Errors in Measurement • A standardis a benchmark used to compare other measures. Calibration is the process of determining how close a measured result is to the true value.
Accuracy is how close your measurement is to the actual value. • Precision is how close a group of measurements are to each other.
Accuracy is how close your measurement is to the actual value. • Precision is how close a group of measurements are to each other.
Significant digits describe how precise a number is. There are several rules to follow when counting significant digits. • Class rule- only use 2 decimal points (unless otherwise instructed) Which ruler will result in greater precision if used to take repeated measurements? Why?