Description acceptable. In one class of these devices, the conversion of AC signals to DC signals causes vibrational rectification error. They're not seismographs, but a type of these devices invented by Lucien LaCoste contain over-coiled springs that behave as if they have (*) "zero-length." Measurement systems consisting of coupled examples of these devices measure a quantity expressed as a 3 by 3 tensor whose components are measured in eotvos (“ert-versh”). Microelectromechanical designs for these devices typically consist of a damped cantilever with a test mass. These devices are the sensors in a car airbag system. The combination of a gyroscope, a magnetometer, and one of these devices compose inertial navigation systems. For 10 points, name these devices used in smartphones to detect shaking and tilting, which measure a quantity with units of meters per second squared. ■END■
ANSWER: accelerometers [accept gravimeters; accept inclinometers; accept gravitational gradiometers; accept answers referring to devices that measure acceleration; accept answers referring to devices that measure gravity or gravitational field or little g or gravitational acceleration; prompt on vibration detectors; prompt on motion sensors or motion detectors; prompt on gyroscopes until read; prompt on pendulums]
<Chen, Physics>
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