a) Explain de-Broglie argument to propose his hypothesis. Show that deBroglie wavelength of photon equals electromagnetic radiation.
b) If, deuterons and alpha particle are accelerated through same potential, find the ratio of the associated de-Broglie wavelengths of two.

Explanation

De-Broglie reasoned out that nature was symmetrical and two basic physical entities –mass and radiation must be symmetrical.If radiation shows shows dual aspect than matter should do so.
De-Broglie equation- `lambda=h//P`
For photon –
P=hv/C
Therefore,h/P=C/v= `lambda`
As `lambda= h//sqrt()2` mk
So,alpha particle will be having shortest de-Broglie wavelength compared to deutrons.