Posted by Jordan on .
MultipleConcept Example 3 provides some pertinent background for this problem. Suppose a single electron orbits about a nucleus containing two protons (+2e), as would be the case for a helium atom from which one of the naturally occuring electrons is removed. The radius of the orbit is 3.09 x 1011 m. Determine the magnitude of the electron's centripetal acceleration.
MultipleConcept Example 3 tells you that the electron mass is 9.11 x 10 ^ 31 kg.
I know what I have to do...
First, use Coulomb's law to find the Force. Then, divide by mass to find the acceleration. But the answer Im getting is HUGE.
This is what I found....
F= 6.94 x 10 ^ 4.
Then, a= 7.62 x 10 ^26.
That is the wrong answer. Please help!!

physics. 
bobpursley,
see above.