CH' 18 SOLIDS

1
CH. 18 SOLIDS SOLID MATERIAL IS MADE UP OF
CRYSTALS REGULAR GEOMETRIC SHAPES DENSITY IS
A MEASURE OF HOW TIGHTLY MATERIALS ARE PACKED
TOGETHER. DENSITY MASS/VOLUME
2
OSMIUM IS THE DENSEST SUBSTANCE ON EARTH. LIST OF
DENSITIES IS ON P. 261 DENSITY IS MEASURED IN
g/cm3 THE DENSITY OF WATER IS 1g/cm3 WEIGHT
DENSITY IS WHEN WE COMPARE THE WEIGHT OF A
SUBSTANCE TO THE VOLUME.
3
SPECIFIC GRAVITY IS WHEN WE COMPARE THE DENSITY
OF WATER TO THE DENSITY OF OTHER
OBJECTS. ELASTICITY IS WHEN AN OBJECT STRETCHES
WHEN ACTED ON BY A FORCE BUT THEN RETURNS TO ITS
ORIGINAL SHAPE WHEN THE FORCE IS REMOVED.
4
AN OBJECT IS INELASTIC IF IT DOES NOT RETURN TO
ITS ORIGINAL SHAPE. THE AMOUNT THAT A SPRING WILL
STRETCH IS CALLED HOOKES LAW FORCE IS
PROPORTIONAL TO THE SPRING STRETCH THE POINT AT
WHICH PERMANENT DISTORTION OCCURS IS CALLED THE
ELASTIC LIMIT.
5
COMPRESSION IS WHEN ATOMS ARE PRESSED CLOSER
TOGETHER. TENSION IS WHEN ATOMS ARE STRETCHED
APART. METAL BEAMS ARE OFTEN FORMED AS THE LETTER
I CALLED I-BEAMS THE FLANGES ARE STRETCHED
AND/OR COMPRESSED.
6
THE CENTER REGION IS LOW STRESS USED TO HOLD THE
TOP AND BOTTOM. IT IS AS STRONG AS IF IT WERE
SOLID WITH LESS WEIGHT. SCALING THE STUDY OF
HOW SIZE AFFECTS THE RELATIONSHIP BETWEEN WEIGHT,
STRENGTH, AND SURFACE AREA.
7
AS AN OBJECT GROWS PROPORTIONATELY IN ALL
DIRECTIONS THE INCREASE IN VOLUME IS GREATER THAN
THE INCREASE IN SURFACE AREA. AREA LENGTH X
WIDTH CM2 SURFACE AREA ADD AREA OF EACH SIDE
CM2 VOLUME LENGTH X WIDTH X HEIGHT CM3