The enthalpy change $\left( \Delta H \right)$ for the reaction,$N_{2(g)} + 3H_{2(g)} \to 2NH_{3(g)}$ is $-92.38 \ kJ$ at $298 \ K$. The internal energy change $\left( \Delta U \right)$ at $298 \ K$ is ........ $kJ$.

The species having tetrahedral shape is

$\int_0^\pi \frac{\theta \sin \theta}{1+\cos ^2 \theta} d \theta$ is equal to

The ratio of angular speeds of the minute hand and the hour hand of a watch is:

$A$ block of mass $2 \ kg$ is tied to one end of a $2 \ m$ long metal wire of $1.0 \ mm^2$ area of cross-section and rotated in a vertical circle such that the tension in the wire is zero at the highest point. If the maximum elongation in the wire is $2 \ mm$, the Young's modulus of the metal is (Acceleration due to gravity $= 10 \ ms^{-2}$)

$A$ ray of light is incident on an equilateral glass prism placed on a horizontal table. For minimum deviation,which of the following is true?