In 1924 Louis de Broglie theorized that not only light posesses both wave and particle properties, but rather particles with mass - such as electrons - do as well. The wavelength of these 'material waves' - also known as the de Broglie wavelength - can be calculated from Planks constant \(h\) divided by the momentum \(p\) of the particle. In the case of electrons that is $$\lambda_{\text{de Broglie}} = \frac {h}{p_\text e}=\frac {h}{m_\text e\cdot v_\text e}$$ The acceleration of electrons in an electron beam gun with the acceleration voltage \(V_{\rm{a}}\) results in the corresponding de Broglie wavelength $$\bbox[8px,border:2px solid red]{\lambda_{\text{de Broglie}} = \frac {h}{m_\text e\cdot \sqrt{2\cdot \frac{e}{m_\text e}\cdot V_{\text a}}}=\frac {h}{\sqrt{2\cdot m_\text e \cdot e\cdot V_{\text a}}}}$$ Proof of the de Broglie hypothesis will be experimentally demonstrated with the help of an electron diffraction tube on the following pages. For electons with acceleration voltage \(V_{\rm{a}}\), the following constansts will be used to calculate the de Broglie wavelengths: Note: The input only allows an acceleration voltage up to \(V_{\rm{a}}=100000\,\rm{V}\). For higher acceleration voltage relativistic calculation should be used. No worries! We‘ve got your back. Try BYJU‘S free classes today! No worries! We‘ve got your back. Try BYJU‘S free classes today! No worries! We‘ve got your back. Try BYJU‘S free classes today! Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses Open in App Suggest Corrections 0 Text Solution Solution : Here, `V=100` Volts.The de- Broglie wavelength `lambda " is " lambda =(1.227)/(sqrt(V))nm`. <br> `=(1.227)/(sqrt(100))=(1.227)/(10) =0.1227=0.123 nm`. <br> The value of de Broglie wavelength is associated with the wavelength of X-ray. |