Two electrons, labelled A and B, move along the same straight line with speeds v and 2v respectively.
a. (i) Using the concept of matter waves, explain qualitatively how the de Broglie wavelength of electron B compares with that of electron A.
b. (ii) If the wavelength associated with electron A is 1.2nm, find the wavelength for electron B.
c. (iii) Briefly justify why doubling the speed does not double the wavelength but changes it in a different proportion.