1. 11:52am
DURING:
11:45am
Weight: 2470g
Volume: 3350mL
FINAL/AFTER:
12:50pm
Final Weight: 3475g
Volume: 3350mL

2. DENSITY & BUOYANCY

3. BUOYANCY = the ability to float in a fluid.
Examples of fluids = water, air
BUOYANT FORCE = the upward force that acts on a submerged object.
It acts opposite of gravity

4. THE BIGGER FORCE WINS, SO THE BLOCK SINKS
WEIGHT OF OBJECT
THE BIGGER FORCE
WINS, SO THE BLOCK
SINKS
BUOYANT
FORCE

5. Which one is easier to pick up?
Why?

6. This beach ball floats.
Why?

7. Because the Buoyant Force is greater than the weight of the ball.

8. ARCHIMEDES’ PRINCIPLE
The buoyant force acting on a submerged object is equal to the weight of the fluid the object displaces.

10. ARCHIMEDES’ PRINCIPLE states that the WEIGHT of the amount of water displaced is equal to the BUOYANT FORCE.

12. A WHICH ONE IS MORE LIKELY TO FLOAT?
Mass = 90 kg
Mass = 90 kg B A
WHICH ONE IS MORE
LIKELY TO FLOAT?

13. DENSITY
DOESN’T DENSITY HAVE SOMETHING TO DO WITH IF SOMETHING SINKS OR FLOATS?

14. KEY TERMS for explanation
In our experiment the bread ______________, I know this because I observed....
In our experiment the bread _______________, because….
KEY TERMS for explanation
Density
Mass
volume
Water
Buoyant/buoyancy
Float/sink
Bread buoyancy

15. 11:52am
DURING:
11:45am
Weight: 2470g
Volume: 3350mL
FINAL/AFTER:
12:50pm
Final Weight: 3475g
Volume: 3350mL

16. d = m (grams)/ v (cubic centimeters(cm3)/milliliters(mL))
DENSITY
d = m (grams)/ v (cubic centimeters(cm3)/milliliters(mL))
DENSITY OF WATER = 1 g/cm3
If the object has a higher density, it sinks.
If the object has a lower density, it floats.
if the object has the same density, it flinks (floats in the middle of the water).

17. SO THE BEACH BALL FLOATS. WATER DENSITY & BUOYANCY
Having a lower density than water means that the beach ball’s buoyant force is higher than the weight of the beach ball.
SO THE BEACH
BALL FLOATS.
WATER

18. DENSITY & BUOYANCY SO THE CINDER BLOCK SINKS. WATER
Having a higher density than water means that the cinder block’s buoyant force is lower than the weight of the cinder block.
SO THE CINDER
BLOCK SINKS.
WATER

19. DENSITY & BUOYANCY SO THE BOOT NEITHER SINKS NOR FLOATS, IT FLINKS
Having the same density as water means that the boot’s buoyant force is equal to the weight of the boot.
SO THE BOOT
NEITHER SINKS
NOR FLOATS, IT
FLINKS
WATER

20. m d = v CHANGING DENSITY You can change an object’s density by:
Increasing its mass, which _________________ its density
Decrease its mass, which _____________________ its density
Increasing its volume, which __________________ its density
Decrease its volume, which __________________ its density m v
d =

22. Weight is less than the buoyant force.
AN OBJECT FLOATS
CAUSES:
Weight is less than the buoyant force.
Object is less dense than the fluid
Object decreases its mass and becomes less dense than the fluid.
Object increases its volume and becomes less dense than the fluid.

23. Weight is greater than the buoyant force.
AN OBJECT SINKS
CAUSES:
Weight is greater than the buoyant force.
Object is denser than the fluid
Object increases its mass and becomes denser than the fluid.
Object decreases its volume and becomes denser than the fluid.