Q.

The minimum wavelength of X-rays produced by an electron accelerated through a potential difference of V volts is proportional to          [2023]

1 1V  
2 V2  
3 V  
4 1V  

Ans.

(4)

Energy of X-ray = hυ=hcλ

As K.E is maximum, thus λ is minimum.

So, energy of emitted X-ray = energy of electron

hcλmin=eVλmin=hce×1Vλmin1V