Question
Explain the unit of energy $e{V}$ (electron volt) and define 1 eV .
✓
Answer
→$e V$ is a smallest unit of energy. It is commonly used in atomic and nuclear physics.
→The energy gained by accelerating an electron with a potential difference of 1 volt is called 1 eV
→Energy gained by electron,
$K =q V \quad(\because w=\Delta K = V q)$
$\therefore \quad K =e V \quad(\because q=e=$ charge of electron $)$
$K =1.6 \times 10^{-19} \times 1$
$\therefore \quad K =1.6 \times 10^{-19} J$
$\therefore \quad K =1 eV$
$\therefore 1 eV =1.6 \times 10^{-19} J$
→The energy gained by accelerating an electron with a potential difference of 1 volt is called 1 eV
→Energy gained by electron,
$K =q V \quad(\because w=\Delta K = V q)$
$\therefore \quad K =e V \quad(\because q=e=$ charge of electron $)$
$K =1.6 \times 10^{-19} \times 1$
$\therefore \quad K =1.6 \times 10^{-19} J$
$\therefore \quad K =1 eV$
$\therefore 1 eV =1.6 \times 10^{-19} J$
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