Question

If alpha, beta and gamma rays carry same momentum, which has the longest wavelength 

(a) alpha rays 

(b) beta rays 

(c) gamma rays 

(d) none, all have same wavelength.

Answer 1

The correct option is (d) none, all have same wavelength.

Explanation:

If the momentum of α and β particles are p, if this is also equal to hv/c of the photon - γ-rays.

λ_{de Broglie} = h/p

As p is the same, the wavelength will be the same. For α and β particles, they are de Broglie waves and in the case of photons (γ-rays), it is the wavelength of the associated electromagnetic wave.