110509,110510 Class #4

Matter=anything that has mass and takes up space (volume)


Volume=measure of how much space an object takes up
(common measurements-cm³,m³,km³,mL,L)


How to measure?
-regular shaped object (rectangle)
*use a formula = volume= length x width x height


-liquid
*use glassware....graduated cylinder!! (we have to look at meniscus)



-irregular shaped object
*use the principle of displacement
volume of the object=(Volume of object + water)-volume of original water


Mass=a measure of how much matter an object contains
(common measurement=kg,g,ton,mg)
*mass never change!!!
How to find it??-->scale


Weight=is a direct measurement of the force(full) of gravity on an object
(common measurement=Newton (N))
How to find??-->Force of gravity=weight=mass X g
*gravity of Earth=g=9.81m/s²


*****1N=1(kg x meter) /s²


Density=mass per unit volume, how much mass something has compared to its volume
How to find??-->use a formula - density=mass/volume
units:kg/cm³, g/m³, g/mL, kg/L, g/cm³, kg/m³...


Buoyancy=is a force=is the upward force on an object in a fluid

common measurment-Newtons

How to Find?-Archimedes Principle 
*The weight of the liquid that an object displaces when placed in a liquid is equal to the buoyant force (Fb)
-Floating or submersed objects

Fb=Density of liquid x Volume of liquid x g

ex1)Force of Buoyancy (of eraser)

       D=m/V

       m=DV

       m=(1.00g/mL)x7mL
          =7g

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Fg=m x g
    =0.007kg x 9.81m/s²
   =0.0687 N
   =Force of Buoyant

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Fg of eraser=mg
                  =0.008kg x 9.81m/s²
                  =0.785 N     

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Positive Buoyancy the tendency of an object to rise in a fluid because the object weighs less than the fluid it displaces

Negative Buoyancy the tendency of an object to sink in a fluid because the object weighs more than the fluid it displaces

Neutral Buoyancy the tendency of an object to remain level in a fluid because the object weighs the same as the fluid it displaces

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Why things FLOAT??


DENSITY!!

things that are less dense floats on the things that are more dense

* more dense=more force of buoyancy
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*1000mL=L
 1000cm³≠m³
*mL=cm³
 L≠m³