If travelling at same speeds, which of the following matter waves have the shortest wavelength?
o According to de-Broglie, 
where 
is the wavelength of a material particle, m is the mass and v is the velocity of the particle having dual nature, his plank’s constant.
o Hence, the wavelength is directly related to the mass of a particle and the relation is inversely proportional; 
i.e. greater the mass shorter will be the wavelength. And amongst the given particles the alpha particle has the greatest mass, therefore, it will have the shortest wavelength.
Other 3 options (i) Electron (iii) Neutron
(iv) Proton are incorrect.
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