An electron is travelling with a velocity v in free space and when it enters a medium, its velocity is reduced by 20%. The de Broglie wavelength of electron in the medium is αλ0, where λ0 is its de Broglie wavelength in free space. The value of α is _______.
Held on 5 Apr 2026 · Verified 6 Jul 2026.
1.20
1.0
1.25
0.75
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