1. Archimedes’ Principle
Goal: Students will be able to calculate density, describe buoyant force, and explain Archimedes’ principle

2. Density Density is: mass per unit volume density is calculated:
density = mass
volume
every substance has its own density

3. Density is used to predict whether an object will sink or float in a fluid
Objects that are more dense will sink
objects that are less dense will float

4. Buoyant Force: the upward force that all fluids exert on all matter.
Buoyant force opposes gravity
That is why you feel lighter in water

5. An object in a fluid has two forces acting on it:
Gravity (down)
Buoyant force (up)
If weight is > buoyant force the object will sink.
If the weight is < the buoyant force, the object will float

7. Archimedes’ Principle
buoyant force on an object = weight of the volume of fluid the object displaces
Why do boats float?