Which of the following hydrides has the lowest boiling point?

Which air pollutant is responsible for the Bhopal gas tragedy?

The $pH$ of water is $7$. When a substance $Y$ is dissolved in water,the $pH$ becomes $13$. The substance $Y$ is a salt of

$A$ long straight wire carrying a current of $30 ~A$ is placed in an external uniform magnetic field of induction $4 \times 10^{-4} ~T$. The magnetic field is acting parallel to the direction of current. The magnitude of the resultant magnetic induction in tesla at a point $2.0 ~cm$ away from the wire is
$\left(\mu_0=4 \pi \times 10^{-7} ~H/m\right)$

$A$ pair of substances which gives the same products on reaction with water is

The potential energy for a force field $\vec{F}$ is given by $U(x, y) = \cos(x + y)$. The force acting on a particle at the position given by coordinates $(0, \pi/4)$ is: