Which of the following hydrides has the lowest boiling point?

Explain the structures of diborane and boric acid.

$A$ body of mass $2 ~kg$ starts from rest and moves with uniform acceleration. It acquires a velocity $20 ~ms^{-1}$ in $4 ~s$. The power exerted on the body in $2 ~s$ in watts is

Three point charges $+q, -2q$ and $+q$ are placed at points $(x = 0, y = a, z = 0)$,$(x = 0, y = 0, z = 0)$ and $(x = a, y = 0, z = 0)$ respectively. The magnitude and direction of the electric dipole moment vector of this charge assembly are

The transition from the state $n = 4$ to $n = 3$ in a hydrogen-like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition:

The radius of gyration of a uniform thin rod of length $L$ about an axis passing normally through its centre of mass is: