In the given reaction,$A$ is:
$A$ $\xrightarrow{\text{Reduction}} B$ $\xrightarrow{HNO_2} C_2H_5OH$

An oscillator is nothing but an amplifier with

$A$ block of $3\,kg$ is initially in equilibrium and is hanging by two identical springs $A$ and $B$ as shown in the figure. If spring $A$ is cut from the lower point at $t=0$,then find the acceleration of the block in $m/s^2$ at $t=0$. (Take $g = 10\,m/s^2$)

If $\frac{\tan 3A}{\tan A} = a$,then $\frac{\sin 3A}{\sin A}$ is equal to

The diameter of the objective of a telescope is $1 \ m$. Its resolving limit for light of wavelength $4538 \ \mathring{A}$ will be:

$A$ $x : 1$ molar mixture of $He$ and $CH_4$ is contained in a vessel at $20 \ bar$ pressure. Due to a hole in the vessel,the gas mixture leaks out. If the composition of the mixture effusing out initially is $8 : 1$,then the value of $x$ will be