Key Terms & Ideas:
Ideas
1. How are your ears involved in balancing your body & maintaining equilibrium?
2. What part of the brain controls muscle coordination & balance? Where in the
brain is this part located?
3. What is velocity?
4. What is acceleration?
Activity – Simulating the Inner Ear
Fill your container about half-way with water (fluid), and place one drop of
food dye in it.
Place a few otoliths (small squares of paper) on the surface of the water.
SEAL the top of the container.
By sliding (not shaking), try to determine what motion would cause the water
to appear like these diagrams – there are 2 ways to get each!:
Motion 1: ____________________________ Motion 1:__________________________
Motion 2:____________________________ Motion 2: _________________________
Motion 1: _______________________________________
Motion 2: _______________________________________
Now, using your definition of acceleration, describe the motions of the three
situations (example: getting
getting faster is the same as increasing acceleration)
acceleration)
1.______________________________________________________________________
2. _____________________________________________________________________
3. _____________________________________________________________________
Relate velocity to acceleration:
(Circle your choice)
Hint: Ask yourself “Is there a change in velocity?”
When velocity is zero, acceleration is:
zero
increasing
at a constant #
decreasing
When velocity is at a constant number (steady at 2mph), acceleration is:
zero
increasing
at a constant #
decreasing
When velocity is constantly increasing by the same amount (getting 2mph faster each
second), acceleration is:
zero
increasing
at a constant #
decreasing
When velocity is constantly increasing by a greater amount (getting 2mph faster in
the first second, then 3mph faster in the next second…), acceleration is:
zero
increasing
at a constant #
decreasing
When velocity is constantly decreasing by a smaller amount (getting 3mph slower in
the first second, then 2mph slower in the next second…), acceleration is:
zero
increasing
at a constant #
decreasing
Drawing graphs: Draw a line on the graph that shows how acceleration changes as
time increases
increases:
Moving at the same speed over time
Getting faster & faster over time
Accel.
Accel.
Time
Time
Getting slower & slower over time
Accel.
Time
You just graphed acceleration! You can do this with any accelerating object, such as
a car, spaceship, running hippopotamus, etc.
etc.
Whew! That took a lot of interpretation! And your brain is doing all this work every
time you move!
Reflection Questions: Answer in the space below the question:
question:
1. The fluid in your ears creates a “graph” of acceleration over time every time
you move. Why is it important that your brain interprets this graph the right
way?
2. Where in your body would messages be sent after your brain interprets
acceleration or direction?
Refer to the graphs on the first page to answer #3-5
3. How might your body respond to the motion in situation 1?
4. How might your body respond to the motion in situation 2?
5. How might your body respond to the motion in situation 3?
6. When might this information apply to “real-life”?