A particle having electric charge 3 10-19 C and mass 6 10-27 kg is accelerated by applying an electric potential of 1.21 V. Wavelength of the matter wave associated with the particle is 10-12 m. The value of is . (Take Planck's constant = 6.6 10-34 J s)
Answer
10
Solution
Kinetic energy gained: K = qV
p = 2mK = 2mqV
2mqV = 2 6 10-27 3 10-19 1.21
= 4.356 10-45
p = 6.6 10-23 kg m s-1
de Broglie wavelength: = hp = 6.6 10-346.6 10-23
= 10-11 m = 10 10-12 m
= 10
Answer: 10