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a) Current through the tube is given by I = ne, where n- number of electrons striking target per second and e- electronic charge ( e = 1.6 × 10-19coulombs) So, n = 1/e = (4.0 × 10-3) / 1.6 × 10-19 = 2.5 × 1016 electrons.
b) Kinetic energy = electrical energy ½ mev2 = eV, then v =$\sqrt{\frac {2ev}{me}}$ = 2.13 × 108 m/s.
Mutiso answered the question on October 16, 2018 at 19:11
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