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**1. Homework Statement**

An electron is rotating around a proton (at rest) in a perfect circular orbit. If the radius of the orbit is r=10^-10 m, how long is the rotation period [hint: the radial acceleration is entirely due to the electric force]

k=9*10^9

q=1.6*10^-19

**2. Homework Equations**

1. F=(k*q^2)/r^2

2. a

_{rad}=(angular velocity)^2*r

**3. The Attempt at a Solution**

I found the force by equaiton 1., and I got 2.3*10^-8 N ((9*10^9)(1.6*10^-19)^2))/((10^-10)^2)

I tried equation 2. to get (angular velocity)=sqrt(F/r) and got 15.2 rad/s

This means that it is 2.4 rev/s (by dividing by 2pi) and 0.41 seconds per orbital period.

That is like the world's slowest electron. Where did I go wrong?