I'm trying to solve this problem correctly, but my calculations yield a different result than the correct answer according to my professor.(adsbygoogle = window.adsbygoogle || []).push({});

In a semi-classical model of the neutral hydrogen atom, an electron of charge -e and of mass 9.1*10^-31 undergoes uniform circular motion around the much more massive proton with charge +e. The radius of the electron's orbit is 5.3*10^-11 m. The speed of the electron in its orbit is ____ m/s.

When I solve the equation I get ((1.6*10^-19)^2/(8.99*10^9 * 5.3*10^-11 * 9.1*10^-31))^(1/2) = 2.43*10^-4 m/s, however they say the correct answer is 2.2*10^6 m/sCode (Text):(Force Elec) = (m * a)

=> e^2/(4*pi*E0*radius^2) = mass*velocity^2/radius

=>velocity = (e^2/(4*pi*E0*radius*mass))^(1/2)

where 1/(4*pi*E0) = 8.99*10^9 Nm^2/C^2 and e = 1.602*10^-19

Maybe I'm doing something wrong? I would hope the prof did everything correctly.

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# Homework Help: Uniform circular motion question

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