Potential Difference of 1200 V Gives Electron 1200 eV Kinetic Energy

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An electron accelerated through a potential difference of 1200 V gains kinetic energy equivalent to 1200 eV. This is because an electron-volt is defined as the energy gained by an electron when it moves through a one-volt potential difference. The relationship between kinetic energy and potential difference can be expressed using the equation 1/2mv^2 = qV, where q is the charge of the electron and V is the voltage. Understanding that 1 V corresponds to 1 Joule per Coulomb helps clarify how energy is calculated in this context. Thus, the kinetic energy of the electron after acceleration is indeed 1200 eV.
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An electron is accelerated from rest through a potential difference 1200 V. Give the electron's kinetic energy after this acceleration in electron-volts?

----I know the answer is 1200 eV but if someone could explain how to get the answer?? And how do I apply 1/2mv^2=qV
 
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The electron-volt is a unit of energy. It's the energy obtained by an electron falling through a one volt electrical potential difference.

Remember that electrical potential is measured in Volts, and that the Volt can be broken down further in terms of units:

[Volt] = \frac{[Joule]}{[Coulomb]}

The electron has a charge in coulombs. The field bestows Volt joules per coulomb when it passes through.
 
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