An electron moves with a speed of 2.00 x 10(^7) ms(^{-1}) in an orbit in a uniform magnetic field of 1.20 x 10(^{-3}) T. Calculate the radius of the orbit. [Mass of an electron = 9.11 x 10(^{-3}) kg; charge on an electron = 1.61 x 10(^{-19})C]
Explanation
(frac{Mv^2}{r}) = qvB
r = (frac{MV^2}{qVB} = frac{9.11 times 10^{31} times (2.00 times 10^7)^2}{1.61 times 10^{-19} times 2.00 times 10^7 times 1.2 times 10^{-3}})
= 9.43 x 10(^{-2})