Net Work & Kinetic Energy Video Lessons

Concept

# Problem: An electron has been accelerated from rest through a potential difference of 800 V.a. What is the electron's kinetic energy, in electron volts?b. What is the electron's kinetic energy, in joules?d. What is the electron's speed?

###### FREE Expert Solution

The kinetic energy of electrons in electron volts:

$\overline{){\mathbf{K}}{\mathbf{=}}{\mathbf{e}}{\mathbf{V}}}$, where K is the kinetic energy, e is the electron charge, and V is the potential difference.

Kinetic energy, in terms of speed, is expressed as:

$\overline{){\mathbf{K}}{\mathbf{=}}\frac{\mathbf{1}}{\mathbf{2}}{{\mathbf{mv}}}^{{\mathbf{2}}}}$, where m is mass and v is the speed.

We also need to remember that:

1eV = 1.6 × 10-19 J

a.

We use the kinetic equation K = eV

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###### Problem Details
An electron has been accelerated from rest through a potential difference of 800 V.

a. What is the electron's kinetic energy, in electron volts?

b. What is the electron's kinetic energy, in joules?

d. What is the electron's speed?