Main Page | See live article | Alphabetical index The Time of Flight method of measuring particle mass is done as follows. A particle of known electrical charge and an unknown mass enters a mass spectrometer and is accelerated by a known electrical force. By knowing the electric force (generated by the spectrometer) and the acceleration of the particle one can then find the mass of the unknown particle. This method of analysis is a powerful tool for finding the atomic composition of individual molecules. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.