Unit deflective charge

U.D.C. (Unit Deflective Charge). The unit deflective charge for an expl is the wt of the expl that has been found to deflect the pendulum of the BuMines ballistic pendulum to the same degree that a standard wt of BuMines standard PTSS Dynamite (see Vol 1, VII-VIII under Ballistic Pendulum Test) has deflected it in a previous test. The U.D.C. for permissible expls shall not exceed 454g (1 lb)... 

Unit Deflective Charge (U.D.C.). See under UJXC. (Unit Deflective Charge) in this Vol... 

As the charge and mass of the a-particles are known (they are He++ ions, for which M = E 2e) and their velocities can be determined from deflection experiments, the formula can be used to find the nuclear charge Z. For this we need only know the number of scattering atoms per unit volume and count the number of a-particles in the presence and absence of the scattering layer. For example, accurate experiments by Chadwiclv gave the following values for Z ... 

Originally atoms were thought to be the smallest unit of matter, but in the late nineteenth century experiments allowed scientists to finally probe inside atoms. Some of these first experiments were carried out by the British physicist J. J. Thomson, who discovered the electron. He noticed that the rays (actually rays of electrons, though he didn t know it at the time) were deflected by electrically charged plates and concluded that these rays must consist of charged particles that were much smaller than atoms themselves. 

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