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An alpha particle is made to move through a potential difference of 10⁶ V. What kinetic energy does it gain?

1. 1 MeV
2. 2 MeV
3. 4 MeV
4. 8 MeV

Correct answer: 2 MeV

Solution

Kinetic energy gained = qV. An alpha particle has charge 2e, so KE = 2e * 10^6 V = 2x10^6 eV = 2 MeV.

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