Back to: Multiplier Event Luxembourg
The Circuit Playground Express board will be turned into an inclinometer in the following activity. An inclinometer is a device that determines the angle of elevation between an observer’s eye and the top of an object situated at a certain distance from the observer. With this information and some right-angle math, the height of objects can be determined approximately.
- \(d\) represents the distance between the human and the tree,
- \(e\) represents the eye level,
- \(h\) represents the tree height,
- \(h-e\) represents the tree height above eye level, and
- \(\alpha\) represents the angle between the imaginary horizontal ray at eye level and the imaginary ray from the eyes to the top of the tree.
Therefore, the accelerometer, a sensor situated in the very centre of the Circuit Playground Express board, will be used. According to its name, an accelerometer measures acceleration. Acceleration occurs when the velocity of something changes, such as a Circuit Playground Express board at rest, is suddenly moved. However, even a Circuit Playground Express board sitting still on the desk seems to be undergoing an acceleration, the acceleration of gravity (\(g\)); its accelerometer reads \(9.81 \frac{\text{m}}{\text{s}^2}\). Just like the force of gravity generates a straight downward acceleration, normal force generates an upward acceleration (but perpendicular to the desk). The accelerometer can tell the amount of gravity (\(g\)) detected in each of the three directions of an XYZ coordinate system the Circuit Playground Express board uses.
