When the kinetic energy of an electron is increased,the wavelength of the associated wave will:

For a moving cricket ball,which of the following statements regarding the de-Broglie wavelength is correct?

The speed of an electron having a wavelength of $10^{-10} \ m$ is ................. $ \times 10^6 \ m/s$.

The velocity of a particle $A$ is $3$ times the velocity of a proton. If the ratio of the de Broglie wavelengths of the particle $A$ and the proton is $3:2$,the mass of the particle $A$ is (where $m_{p}$ is the mass of the proton).

What are called matter waves? Name the devices which employ the use of these matter waves.

Calculate the $(a)$ momentum,and $(b)$ de Broglie wavelength of the electrons accelerated through a potential difference of $56 \; V$.