Answer
$K.E=2.09\times 10^{-22}J$
Work Step by Step
We can determine K.E from the formula:
$K.E=\frac{1}{2}mv^2$....................eq(1)
The centripetal force is given as
$F=\frac{mv^2}{r}$
This means that eq(1) can be re-written as:
$K.E=\frac{1}{2}\frac{mv^2}{r}\times r$
$K.E=\frac{1}{2}\times F\times r$
We plug in the known values into this equation to obtain:
$K.E=\frac{1}{2}\times 1.60\times 10^{-17}\times 26.1\times 10^{-6}$
$K.E=2.09\times 10^{-22}J$
