In good conductors of electricity,the type of bonding that exists is

$A$ transformer works on the principle of

The correct order of reactivity of hydrogen halides with ethyl alcohol is

From a disc of radius $R$,a concentric circular portion of radius $r$ is cut out so as to leave an annular disc of mass $M$. The moment of inertia of this annular disc about the axis perpendicular to its plane and passing through its centre of gravity is

The inverse of the matrix $\left[\begin{array}{ccc}7 & -3 & -3 \\ -1 & 1 & 0 \\ -1 & 0 & 1\end{array}\right]$ is

$A$ ball is projected with velocity $V_0$ at an angle of elevation $30^\circ$. Mark the correct statement.