It is a device which is used to measure proper acceleration of an object. It is to be noted that the proper acceleration which is measured by the accelerometer is not essentially the rate of change of velocity i.e. coordinate acceleration.
The accelerometer just measures the acceleration that is associated with the observable weight which is experienced by test mass in the frame of reference of the device. For instance, if the accelerometer is placed on the surface of the earth, it will show the measurement of the acceleration as 35.303 km/h. On the other hand, if it is place somewhere in the space, it will show zero in its measurement.
The accelerometer is also used to measure the g-force. There are many different accelerometers which are used by the scientists or other professionals according to their requirements. For example, a highly sensitive accelerometer is used as a component of inertial navigation system in missiles or aircrafts.
Furthermore, accelerometers are used to detect vibrations in rotating machines. Besides that, they are also used in digital cameras and tablet computers to display the images in an upright direction.
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It is a device which is used to measure or maintain orientation and works on the principles of angular momentum. It is spinning wheel in which the axle can assume any orientation. The orientation changes in a different direction because of an external torque.
The orientation of Gyroscope remains almost fixed despite the motion of mounting platform due to a gimbal that minimises the effect of external torque.
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