In a transformer,the number of turns in the primary coil is $140$ and that in the secondary coil is $280$. If the current in the primary coil is $4 \, A$,then the current in the secondary coil is......$A$.

Two coherent sources whose intensity ratio is $64: 1$ produce interference fringes. The ratio of intensities of maxima and minima is

Which of the following is correctly matched?

Which of the following equations is a balanced one?

$A$ molecule $(X)$ has $(i)$ four sigma bonds formed by the overlap of $sp^2$ and $s$ orbitals,$(ii)$ one sigma bond formed by $sp^2$ and $sp^2$ orbitals,and $(iii)$ one $\pi$ bond formed by $p_z$ and $p_z$ orbitals. Which of the following is $X$?

The number of values of $x$ in the interval $[0, 3\pi]$ satisfying $2 \sin^2 x + 5 \sin x - 3 = 0$ is