JEE MAIN 2026 ONLINE 22ND JANUARY EVENING SHIFT

Two masses $m$ and 2 m are connected by a light string going over a pulley (disc) of mass 30 m with radius $r=0.1 \mathrm{~m}$. The pulley is mounted in a vertical plane and it is free to rotate about its axis. The 2 m mass is released from rest and its speed when it has descended through a height of 3.6 m is

$\_\_\_\_$ $\mathrm{m} / \mathrm{s}$. (Assume string does not slip and $\mathrm{g}=10 \mathrm{~m} / \mathrm{s}^2$ )

Suppose $\mathrm{a}, \mathrm{b}, \mathrm{c}$ are in A.P. and $\mathrm{a}^2, 2 \mathrm{~b}^2, \mathrm{c}^2$ are in G.P. If $\mathrm{a}<\mathrm{b}<\mathrm{c}$ and $\mathrm{a}+\mathrm{b}+\mathrm{c}=1$, then $9\left(\mathrm{a}^2+\mathrm{b}^2+\mathrm{c}^2\right)$ is equal to $\_\_\_\_$ .

Among the following oxides of $3 d$ elements, the number of mixed oxides are $\_\_\_\_$ .

$$\mathrm{Ti}_2 \mathrm{O}_3, \mathrm{~V}_2 \mathrm{O}_4, \mathrm{Cr}_2 \mathrm{O}_3, \mathrm{Mn}_3 \mathrm{O}_4, \mathrm{Fe}_3 \mathrm{O}_4, \mathrm{Fe}_2 \mathrm{O}_3, \mathrm{Co}_3 \mathrm{O}_4$$

An insulated cylinder of volume $60 \mathrm{~cm}^3$ is filled with a gas at $27^{\circ} \mathrm{C}$ and 2 atmospheric pressure. Then the gas is compressed making the final volume as $20 \mathrm{~cm}^3$ while allowing the temperature to rise to $77^{\circ} \mathrm{C}$. The final pressure is $\_\_\_\_$ atmospheric pressure.

Let S be the set of the first 11 natural numbers. Then the number of elements in $A=\{B \subseteq S: n(B) \geqslant 2$ and the product of all elements of $B$ is even $\}$ is $\_\_\_\_$ .

Consider the following electrochemical cell :

$$\mathrm{Pt}\left|\mathrm{O}_2(\mathrm{~g})(1 \mathrm{bar})\right| \mathrm{HCl}(\mathrm{aq}) \| \mathrm{M}^{2+}(\mathrm{aq}, 1.0 \mathrm{M}) \mid \mathrm{M}(\mathrm{~s})$$

The pH above which, oxygen gas would start to evolve at anode is $\_\_\_\_$ (nearest integer).

$$\left.\left[\begin{array}{ll} \text { Given : } & \mathrm{E}_{\mathrm{M}^{2+} / \mathrm{M}}^{\mathrm{o}}=0.994 \mathrm{~V} \\ & \mathrm{E}_{\mathrm{O}_2 / \mathrm{H}_2 \mathrm{O}}^{\mathrm{o}}=1.23 \mathrm{~V} \end{array}\right\} \text { standard reduction potential } \\ \text {and} \frac{\mathrm{RT}}{\mathrm{F}}(2.303)=0.059 \mathrm{~V} \text {at the given condition}\right]$$