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An electron of mass 'm' with an initial velocity ) 0 v ( i ˆ v v 0 0    enters an electric field k ˆ E – E 0   . If the initial de Broglie wavelength is  0 , the value after time t would be : -

1. 2 0 2 2 2 0 2 0 v m t E e 1  
2. 2 0 2 2 2 0 2 0 v m t E e – 1 
3.  0
4. 2 0 2 2 2 0 2 0 v m t E e 1  

Correct answer: 2 0 2 2 2 0 2 0 v m t E e 1  

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