Class 12th

$100\mathrm{m}\mathrm{L}$ of $0.1\mathrm{M}\mathrm{H}\mathrm{C}\mathrm{l}$  is taken in a beaker and to it $100\mathrm{m}\mathrm{L}$ of $0.1\mathrm{M}\mathrm{N}\mathrm{a}\mathrm{O}\mathrm{H}$  is added in steps of $2\mathrm{m}\mathrm{L}$ and the $\mathrm{p}\mathrm{H}$ is continuously measured. Which of the following graphs correctly depicts the change in  $\mathrm{p}\mathrm{H}$ ?

The compound $\mathrm{A}$  in the following reactions is

An ionic micelles is formed on the addition of: excess water to liquid

The major product in the following reaction is:

Consider the following reaction:

The product ' $P$  ' gives positive ceric ammonium nitrate test. This is because of the presence of which of these  group(s)?

When an object is kept at a distance of $30\mathrm{c}\mathrm{m}$  from a concave mirror, the image is formed at a distance of $10\mathrm{c}\mathrm{m}$ from the mirror. If the object is moved with a speed of 9 $\mathrm{c}\mathrm{m}\mathrm{s}$   , the speed (in $\mathrm{c}\mathrm{m}{\mathrm{s}}^{-1}$  ) with which image moves at that instant is

A galvanometer coil has 500 turns and each turn has an average are of $3*{10}^{-4}{\mathrm{m}}^2$ . If a torque of  $1.5\mathrm{N}\mathrm{m}$ is required to keep this coil parallel to a magnetic field when a current of $0.5\mathrm{A}$  is flowing through it, the strength of the field (in $\mathrm{T}$  ) is

A small bar magnet is moved through a coil at constant speed from one end to the other. Which of the following series of observations will be seen on the galvanometer G attached across the coil?

Three positions shown describe:

(a) the magnet's entry

(b) magnet is completely inside and

(c) magnet's exit

Two resistors $400\mathrm{\Omega }$  and   $800\mathrm{\Omega }$ are connected in series across a  $6\vee$ battery. The potential difference measured by a voltmeter of $10\mathrm{k}\mathrm{\Omega }$ across $400\mathrm{\Omega }$  resistor is close to:

Choose the correct option relating wavelengths of different parts of electromagnetic wave spectrum: