The availability of inexpensive and easy-to-use accelerometer devices, such as a Wiimote, offers many possibilities for fun physics experiments and demonstration projects. A Wiimote can be used for the illustration of Newton’s third law by colliding two Wiimote-attached carts (possibly extendable to a 2D experiment on an air-hockey table), for a simulation of weightlessness during a free fall by dropping a Wiimote, and for the study of an oscillatory motion with a Wiimote-attached pendulum.
Example: 3D inclined plane experiment
The setup of the experiment is simple, only requiring an adjustable ramp (a wooden board and a stand), protractor, rubber bands (to prevent the Wiimote sliding down the ramp), a Wiimote, and a computer for collecting and analyzing the data. The experiment involves placing the Wiimote at various combinations of θ (angle of the incline) and φ (angle of the Wiimote with respect to the direction of the incline) and measuring the force of gravity.
The gravity points toward the floor and is decomposed into three orthogonal directions:
az = g(cosθ),
ay = g(sinθ)(cosφ),
ax = g(sinθ)(sinφ).
When φ=0 (the Wiimote is aligned length-wise along the incline), the setup reduces back to the familiar 2D inclined plane problem with only two relevant directions. The Wiimote data can be compared against the prediction, and also used to show that these three components add up to g. For more information, see The Physics Teacher (2011).