Answer: The speed necessary for the electron to have this energy is 466462 m/s
Explanation:
Kinetic energy is the energy posessed by an object by virtue of its motion.
K.E= kinetic energy = 
m= mass of an electron = 
v= velocity of object = ?
Putting in the values in the equation:
The speed necessary for the electron to have this energy is 466462 m/s
I googled the specific heat capacity for iron so it might be off to the value you might have used, bit it should be close.
To solve the problem, use Kepler's 3rd law :
T² = 4π²r³ / GM
Solved for r :
r = [GMT² / 4π²]⅓
but first covert 6.00 years to seconds :
6.00years = 6.00years(365days/year)(24.0hours/day)(6...
= 1.89 x 10^8s
The radius of the orbit then is :
r = [(6.67 x 10^-11N∙m²/kg²)(1.99 x 10^30kg)(1.89 x 10^8s)² / 4π²]⅓
= 6.23 x 10^11m
