Q.

An electron and an alpha particle are accelerated by the same potential difference. Let λe and λα denote the de Broglie wavelengths of the electron and the alpha particle, respectively, then               [2024]
 

1 λe>λα  
2 λe=4λα  
3 λe=λα  
4 λe<λα  

Ans.

(1)

The de-Broglie wavelength in terms of potential difference is given by,

             λ=h2mqv

For same potential difference,

           λ1m  and  λ1q

So, λe>λα    (mα and qα are greater than me and qe)