The Total solution for NCERT class 6-12
The wavelength of a probe is roughly ameasure of the size of a structure that it can probe in some detail. The quark structureof protons and neutrons appears at the minute length-scale of 10−15 mor less. This structure was first probed in early 1970’s using high energyelectron beams produced by a linear accelerator at Stanford, USA. Guess whatmight have been the order of energy of these electron beams. (Rest mass energyof electron = 0.511 MeV.)
Wavelength of a proton or a neutron, λ ≈10−15 m
Rest mass energy of anelectron:
m0c2 = 0.511 MeV
= 0.511 × 106 × 1.6 × 10−19
= 0.8176 × 10−13 J
Planck’s constant, h = 6.6× 10−34 Js
Speed of light, c = 3 × 108 m/s
The momentum of a protonor a neutron is given as:
The relativistic relation for energy (E)is given as:
Thus,the electron energy emitted from the accelerator at Stanford, USA might be ofthe order of 1.24 BeV.