Answer to Question #92352 in Mechanics | Relativity for Fatima

Question

2) If an electron in copper near the lowest possible temperature has a kinetic energy of 6.6*10^-19, what is the speed of the electron ?

Answer 1

The kinetic energy

$$KE=\frac{mv^2}{2}$$

So, the speed of the electron

$$v=\sqrt{\frac{2KE}{m}}=\sqrt{\frac{2\times 6.6\times 10^{-19}\:\rm{J}}{9.1\times 10^{-31}\:\rm{kg}}}$$

$$=1.2\times 10^6\:\rm{m/s}$$