Which of the following reagents would you use to separate $SO_4^{2-}$ ions from a solution containing a mixture of $SO_4^{2-}$ and $Cl^-$ ions?

Helium gas undergoes a cycle $ABCDA$ (consisting of two isochoric and two isobaric lines) as shown in the figure. The efficiency of this cycle is nearly ..... $\%$ (Assume the gas to be close to an ideal gas).

An electron moves with speed $2 \times 10^5 \ m/s$ along the positive $x$-direction in the presence of a magnetic induction $\vec{B} = \hat{i} + 4\hat{j} - 3\hat{k}$ (in $Tesla$). The magnitude of the force experienced by the electron in Newtons is (charge on the electron = $1.6 \times 10^{-19} \ C$).

$A$ graph of magnetic flux $(\phi)$ versus current $(I)$ is shown for four inductors $A, B, C$ and $D$. Which inductor has the largest value of self-inductance?

The pulleys in the diagram are all smooth and light. The acceleration of $A$ is $a$ upwards and the acceleration of $C$ is $f$ downwards. The acceleration of $B$ is

Consider the general reaction given below at $400 \ K$: $xA_{(g)} \rightleftharpoons yB_{(g)}$. The values of $K_p$ and $K_c$ are studied under the same condition of temperature but variation in $x$ and $y$. $(i)$ $K_p = 85.87$ and $K_c = 2.586$ (appropriate units). $(ii)$ $K_p = 0.862$ and $K_c = 28.62$ (appropriate units). The values of $x$ and $y$ in $(i)$ and $(ii)$ respectively are: