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Sponge: List five scientists you saw in the Mechanical Universe film.

Sponge: List five scientists you saw in the Mechanical Universe film.

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## Sponge: List five scientists you saw in the Mechanical Universe film.

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**Sponge: List five scientists you saw in the Mechanical**Universe film.**These two overlap; the main difference is that physics**always deals with the concept of energy.**mechanics,**thermodynamics, waves, optics, electricity and magnetism, relativity, and nuclear physics. The major areas within Physics are:**Scientific MethodLAWS-describe the relationships between**various phenomena**Boyle’s Law**• Charles’ Law • Cole’s Law**Scientific Law-expressed by wordsLaws in physics-expressed**by math equations**THEORY-reasonable explanation of observed events that are**related.**Theories often involve models.e.g. Atomic**Theory Democritus’ Model Thomson’s Model Rutherford’s Model Bohr’s Model Electron Cloud Model**Hypotheses & InvestigationsFive**Steps Problem Research Hypothesis - extends thinking beyond known facts Experiment Conclusions**Certainty in scienceOne should always question the validity**of scientific Laws, Theories, or Hypotheses.**METRIC SYSTEM - uses a decimal basis for multiples and**fractions of the basic units of measure.**International System of UnitsThe SI system(Systeme**International d’Unites)**Units of measure are used to describe physical**quantities.e.g. the meter is the unit of length**Seven fundamental units of measure:**• 1. length meter • 2. mass kilogram • 3. time second • 4. electric current ampere • 5. temperature kelvin • 6. amount of substance mole • 7. luminous intensity candela**Combinations of these units are used to measure other**physical quantities.(e.g. mass density)These are called derived units.**Modern metric system often called the MKS system.(meter,**kilogram, second)**METERStandard meter was a metal bar until 1960.Now 1 meter =**the distance light travels in a vacuum in 1/299 729 458th of a second. (speed of light is no longer subject to revision)**KILOGRAMMass of the standard kilogram. Only measure that**still is a natural object.**FORCE AND WEIGHTNewton is the accepted unit.Force needed to**accelerate a one kilogram mass by one m/s2.**THE SECONDone second = 9 192 631 770 vibrations of**cesium-133 atoms.**1 ml H2O = 1 cm3 H2O = 1 g H2Oheat required to change temp**of 1 g liquid H2O 1° centigrade (Kelvin) is 1 calorie**It is important to indicate the degree of uncertainty in**measurements so far as it is known.**ACCURACY - the closeness of a measurement to the accepted**value for a specific physical quantity.**absolute error- actual difference between the accepted value**and the measured value.**Ea = |O - A|,whereEa is the absolute error, O is the**observed value, and A is the accepted value.**Relative Error - expressed as a percentage. (often called**percentage error)**Er = (Ea / A) x 100%whereEr is the relative error, Ea is the**absolute error, and A is the accepted value.**PRECISION - the agreement among several measurements that**have been made in the same way.**Absolute deviation-difference between a single measured**value and the average of several measurements made in the same way.**Relative Deviation-the percentage average deviation of a set**of measurements.**Significant Figures - Those digits in a number that are**known with certainty plus the first digit that is uncertain.**RULES:1. all nonzero figures are significant 112.6 ____ sig**figs**RULES:1. all nonzero figures are significant 112.6 Four sig**figs**2. All zeros between nonzero figures are**significant108.005____sig figs**2. All zeros between nonzero figures are significant108.005**Six sig figs**3. Zeros right of a nonzero figure, but left of understood**decimal point, are not significant unless indicated.109 000 _____ sig figs _109 000 _____ sig figs**3. Zeros right of a nonzero figure, but left of understood**decimal point, are not significant unless indicated.109 000 Three sig figs _109 000 _____ sig figs**3. Zeros right of a nonzero figure, but left of understood**decimal point, are not significant unless indicated.109 000 _____ sig figs _109 000 Five sig figs**4. Zeros to the right of a decimal point but to the left of**a nonzero figure are not significant. Zero to the left of decimal point is never significant.0.000 647 _____sig figs**4. Zeros to the right of a decimal point but to the left of**a nonzero figure are not significant. Zero to the left of decimal point is never significant.0.000 647 Three sig figs