Question

Electrons with a speed of 1.0 x 107 m/s strike the screen of a television set. With what kinetic energy does a single electron hit the screen? (mass of electron is 9.11 x 10-31 kg)

Answer 1

The speed of the electron is

`v=\text{ 1}*10^7\text{ m/s}`

The mass of the electron is

`m=\text{ 9.11}*10^(-31)\text{ kg}`

To find the kinetic energy.

Step-by-step explanation:

The kinetic energy can be calculated as

`\begin{gathered} K.E.\text{ =}(1)/(2)mv^2 \\ =(1)/(2)*9.11\text{ }*10^(-31)\text{ kg}*(1*10^7)^2 \\ =4.555\text{ }*\text{10}^{-17\text{ }}J \end{gathered}`