Understanding density
10
Understandin g Densit y
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Transcript of Understanding density
Understanding
Density
What is Density?
• The ratio of the mass of a substance to its volume
D =
– Volume – amount of space an object takes up
– Mass – the amount of matter (stuff) in an object
M
V
What is Density?
– Volume – amount of space an object takes up
– Mass – the amount of matter (stuff) in an object
– So density is the amount of stuff in a certain space….
– The more stuff in a space the higher the density
• Which box has more stuff in it?• Which box has the greatest density?• Why does this box have the greatest
density?
•BECAUSE IT HAS MORE STUFF IN IT!!!
Think about it…
• What is the most dense “phase” of matter?– SOLID….why?
• Has the most “stuff” (matter) in the smallest space
• Huge Balloon versus Golf Ball. Which on is more dense?
• Golf Ball …. Why?• Has the most “stuff” (matter) in the smallest space
Heating an object…Expands- volume increases = more space
Matter – Stuff inside remains the same
Therefore: same “stuff” (matter) in a bigger space = lower density
Temperature & Volume Temperature & Density
temperature temperature
volu
me
dens
ity
Breaking up …
• If you break an object of uniform composition in half, what happens to its density?
MASS = 100 g VOLUME = 10 cm3
DENSITY = 10 g/ cm3
Breaking up …
• If you break an object of uniform composition in half, what happens to its density?
MASS = 50 g VOLUME = 5 cm3 MASS = 50 g VOLUME = 5 cm3
DENSITY = 10 g/ cm3 DENSITY = 10 g/ cm3
WHY – MASS AND VOLUME CHANGE PROPORTIONALLY (EQUALLY)
Breaking up …
• If you break an object of uniform composition in half, what happens to its density?
MASS = 50 g VOLUME = 5 cm3 MASS = 25 g VOLUME = 2.5 cm3
DENSITY = 10 g/ cm3 DENSITY = 10 g/ cm3
