In Young's double slit experiment, in an interference pattern, a minimum is observed exactly in front of one slit. The distance between the two coherent sources is d and $\mathrm{D}_{\text { }}$ is the distance between source and screen. The possible wavelengths used are proportional to

The total energy of a circularly orbiting satellite is

The de-Broglie wavelength $(\lambda)$ of a particle

An incompressible fluid flows steadily through a cylindrical pipe having radius R at point A and $\left(\frac{\mathrm{R}}{3}\right)$ at point B further along the direction of flow of liquid. If the velocity at point A is ' V ' then that at point B is