Introduction
The topic of
relative motion is first introduced. This
involves defining
some physics terms
such as kinematics, scalars and vectors.
Next, an example of relative motion in one dimension is given. The example of 2 vehicles traveling
down a road with different velocities is a simple example to
show. This is then followed by an analysis of the
situation. An explanation is then given on
how to find the
relative velocities from different observers' frames of reference.
First Demonstration is a
typical “river problem” in one
dimension
Using my simulated river, a boat whose motion
is upstream, is simulated. The instructor
and students then
find all the relative velocities of the 3 objects (a person standing on
the
bank of the river, a boat, and a kayaker floating with the current of
the river).
Introduction of two dimensions and relative motion
One
more dimension is then added to the situation. Now
we can simulate at
boat in motion
upstream and across a river. An example of
a boat that is crossing a river is then given. The location where
the boat lands on the other side of the river can then be found. The boat's motion is also found in different
frames of reference.
Second and Third Demonstration
The second demonstration is
a simulation of boat aimed
directly across the river. The resultant
path of the boat is across the river and downstream.
With this simulation we can find the
resultant motion of the boat. With the
third demonstration the goal is to aim the boat upstream so that the
boat’s
motion is directly across the river. These
demonstrations are should numerous times as they are more complex to
understand. In addition, the
demonstration is stopped at
different places to analyze the boat's motion.
Note
It is important to stop the
demonstrations and analyze the
situation. When figuring out the
velocity of an object, start by finding the direction, then the
magnitude. To get a better understanding
of my lesson
plan you can view the powerpoint presentation (PDF form).