At a given instant,block $A$ is moving with a velocity of $5\,m/s$ upwards. What is the velocity of block $B$ at that instant?

The absolute configurations of the two chiral centers in the following molecule are:

$A$ tension of $22 ~N$ is applied to a copper wire of cross-sectional area $0.02 ~cm^2$. The Young's modulus of copper is $1.1 \times 10^{11} ~N/m^2$ and the Poisson's ratio is $0.32$. The decrease in cross-sectional area will be:

$A$ conducting rod of length $2l$ is rotating with constant angular speed $\omega$ about its perpendicular bisector. $A$ uniform magnetic field $\vec B$ exists parallel to the axis of rotation. The $e.m.f.$ induced between two ends of the rod is

The potential difference between $A$ and $B$ in the figure is .............. $V$.

$A$ certain electronic transition from an excited state to the ground state of the $H$ atom in one or more steps gives rise to three lines in the ultraviolet region of the spectrum. How many lines does this transition produce in the infrared region of the spectrum?