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An α-particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of 0.25 Wb/m². The wavelength associated with the particle will be:

1. 1 Å
2. 0.1 Å
3. 10 Å
4. 0.01 Å

Correct answer: 0.1 Å

Solution

The radius of the circular path and the magnetic field allow us to calculate the momentum of the α-particle using the relation r = mv/qB. Using the de Broglie wavelength formula λ = h/p, we find the wavelength to be approximately 0.1 Å.

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