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If the kinetic energy of a free electron doubles, it’s deBroglie wavelength changes by the factor

1. 2
2. 1/2
3. √2
4. 1/√2

Correct answer: 1/√2

Solution

De Broglie wavelength lambda = h/sqrt(2*m*KE). Doubling KE multiplies lambda by 1/sqrt(2).

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