The wave nature of an electron was first given by

Number of waves formed by a Bohr electron in one complete revolution in its third orbit is

The de Broglie wavelengths of two fast moving particles $X$ and $Y$ are $1 \ nm$ and $3 \ nm$ respectively. The mass of $X$ is nine times the mass of $Y$. The ratio of kinetic energies of $X$ and $Y$ is:

$A$ $200 \ g$ golf ball is moving with a speed of $5 \ m$ per hour. The associated wavelength is $(h = 6.625 \times 10^{-34} \ J \ s)$.

The following plot represents the de-Broglie wavelength $(\lambda)$ as a function of $\frac{1}{\sqrt{K.E.}}$ for two particles $A$ and $B$. Identify the correct relation between their masses ($m_A$ and $m_B$).

The velocities of two particles $A$ and $B$ are $0.05 \ ms^{-1}$ and $0.02 \ ms^{-1}$ respectively. The mass of $B$ is five times the mass of $A$. The ratio of their de-Broglie's wavelength is