Question

3. An electron with a mass of 9.11 X 10^-31 kg is moving at a speed of 2.19 X 10 m/s. What is the kinetic energy of the electron?

Answer 1

Answer:

$2.18\times 10^{-30} \:J$

Explanation:

$K.E._{Electron}= \frac{1}{2} mv^2 \\\\

= \frac{1}{2} \times 9.11\times 10^{-31}\times (2.19\times 10)^2 \\\\

=4.555\times 10^{-31}\times 4.7961\times 10^2 \\\\

=4.555\times 10^{-31+2}\times 4.7961 \\\\

=21.8462355\times 10^{-29}\\

=2.18462355\times 10^{-30}\\

=2.18\times 10^{-30} \:J$