Answers

2014-05-19T18:17:25+05:30
T=(2× π×mass)÷(charge*magnetic field)
therefore on putting the values 
mass of electron= 9.1x10^-31
charge on electron= 1.6x10^-19
and B=1.2x10^-5
we get, the ans as 2.977 x 10^-8
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