The qualitative order of de Broglie wavelength for electron, proton and a particle is ${\lambda }_e>{\lambda }_p>{\lambda }_{\alpha }$:

The qualitative order of de Broglie wavelength for electron, proton and a particle is ${\lambda }_e>{\lambda }_p>{\lambda }_{\alpha }$ are, the order of mass of electron, proton and alpha particle is$\mathrm{\alpha }>\mathrm{p}>{\mathrm{e}}^{-}$ hence, order of de-Broglie's wavelength is ${\lambda }_e>{\lambda }_p>{\lambda }_{\alpha }$.

(a) At any given temperature, not all of the particles in a sample of matter have the same kinetic energy. Instead, the particles display a wide range of kinetic energies.

(b)This electron experiences of force F in a uniform magnetic field. On increasing the potential difference to V′, the force experienced by the electron in the same magnetic field becomes 2F.

(c) No. Because the axis is non fixed so the direction of angular velocity parallel to the axis does not remains same and hence linear velocity is also not constant.