An electron accelerated by a p.d of V possess a de-Broglie wavelength λ. If the accelerating potential is increased by a factor 4. The de-Broglie wavelength of the electron will
(1) remain unchanged
(2) becomes 4 times
(3) become double
(4) become halved
Correct option : (4) become halved
Explanation :
When an electron is accelerated through a potential V its energy becomes eV and hence 1/2 mv2 = eV
Hence whenever V is increased by a factor of 4 λ will get halved.
