An electron in a magnetic field has a cyclotron frequency of 8.0 × 10¹² Hz.What is the magnetic field strength? (The mass of an electron is 9.1 × 10^-31kg,and the charge of an electron is 1.6 × 10^-19C. ) A)290 T B)4.5 T C)0.22 T D)0.0035 T

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The cyclotron frequency is given by:$$f_c = \frac{qB}{2\pi m}$$where:* $f_c$ is the cyclotron frequency* $q$ is the charge of the electron* $B$ is the magnetic field strength* $m$ is the mass of the electronSolving for $B$, we get:$$B = \frac{2\pi m f_c}{q}$$Plugging in the given values, we get:$$B = \frac{2\pi (9.1 \times 10^{-31} \text{ kg})(8.0 \times 10^{12} \text{ Hz})}{1.6 \times 10^{-19} \text{ C}} = 0.22 \text{ T}$$Therefore, the correct answer is C.

An Electron in a Magnetic Field Has a Cyclotron Frequency