Column I showns four systems, each of the same length \(L\), for producing standing waves. The lowest possible natural frequency of a system is called its fundamental frequency, whose wavelength is denoted as \(\lambda_f\). Match each system with statements given in Column II describing the nature and wave length of the standing waves.

A series \(R-C\) combination is connected to an \(\mathrm{AC}\) voltage of angular frequency \(\omega=500 \mathrm{rad} / \mathrm{s}\). If the impedance of the \(R-C\) circuit is \(R \sqrt{1.25}\), the time constant (in millisecond) of the circuit is

A projectile is thrown from a point \(\mathrm{O}\) on the ground at an angle \(45^{\circ}\) from the vertical and with a speed \(5 \sqrt{2} \mathrm{~m} / \mathrm{s}\). The projectile at the highest point of its trajectory splits into two equal parts. One part falls vertically down to the ground, \(0.5 \mathrm{~s}\) after the splitting. The other part, \(t\) seconds after the splitting, falls to the ground at a distance \(x\) meters from the point O. The acceleration due to gravity \(g=10 \mathrm{~m} / \mathrm{s}^{2}\).
The value of $t$ is _________.

A person of height $1.6 \mathrm{m}$ is walking away from a lamp post of height $4 \mathrm{m}$ along a straight path on the flat ground. The lamp post and the person are always perpendicular to the ground. If the speed of the person is $60 \mathrm{cm} {\mathrm{s}}^{-1}$, the speed of the tip of the person’s shadow on the ground with respect to the person is _____ $\mathrm{cm} {\mathrm{s}}^{-1}$.

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In the figure a container is shown to have a movable (without friction) piston on top. The container and the piston are all made of perfectly insulating material allowing no heat transfer between outside and inside the container. The container is divided into two compartments by a rigid partition made of a thermally conducting material that allows slow transfer of heat. The lower compartment of the container is filled with \(2\) moles of an ideal monatomic gas at \(700 K\) and the upper compartment is filled with \(2\) moles of an ideal diatomic gas at \(400 K\). The heat capacities per mole of an ideal monatomic gas are \(C_{V}=\frac{3}{2} R, C_{P}=\frac{5}{2} R\), and those for an ideal diatomic gas are \(C_{V}=\frac{5}{2} R, C_{P}=\frac{7}{2} R\).


Question :
Consider the partition to be rigidly fixed so that it does not move. When equilibrium is achieved, the final temperature of the gases will be

A student performed the experiment to measure the speed of sound in air using resonance air-column method. Two resonances in the air-column were obtained by lowering the water level. The resonance with the shorter air-column is the first resonance and that with the longer air column is the second resonance. Then,

Consider a star of mass \(m_2 \mathrm{~kg}\) revolving in a circular orbit around another star of mass \(m_1 \mathrm{~kg}\) with \(m_1 \gg m_2\). The heavier star slowly acquires mass from the lighter star at a constant rate of \(\gamma \mathrm{kg} / \mathrm{s}\). In this transfer process, there is no other loss of mass. If the separation between the centers of the stars is \(r\), then its relative rate of change \(\frac{1}{r} \frac{\mathrm{~d} r}{\mathrm{~d} t}\left(\right.\) in s \(\left.^{-1}\right)\) is given by:
[Note: The original question was awarded bonus marks in the JEE Advanced 2025 exam. We have changed the options to make the question valid and solvable.]

Let $\mathrm{F}\left(\mathrm{x}\right)=\mathrm{ }\underset{\mathrm{x}}{\overset{{\mathrm{x}}^2+\frac{\mathrm{\pi }}{6}}{\int }}2{\cos }^2\mathrm{t}\mathrm{ }\mathrm{d}\mathrm{t}$ for all $\mathrm{x}\mathrm{ }\in \mathbb{R}\mathrm{ }\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{ }\mathrm{f}\mathrm{ }:\mathrm{ }\left[0,\frac{1}{2}\right]\to \left[0,\mathrm{ }\mathrm{\infty }\right)$ be a continuous function. For $\mathrm{a}\in \left[0,\frac{1}{2}\right],$ if ${\mathrm{F}}^{\mathrm{\prime }}\left(\mathrm{a}\right)+2$ is the area of the region bounded by $\mathrm{x}=0,\mathrm{ }\mathrm{y}=0,\mathrm{ }\mathrm{y}=\mathrm{f}\left(\mathrm{x}\right)\mathrm{ }\mathrm{a}\mathrm{n}\mathrm{d}\mathrm{ }\mathrm{x}=\mathrm{a},$ then $\mathrm{f}\left(0\right)$ is

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If a continuous \(f\) defined on the real line \(R\), assume positive and negative values in \(R\), then the equation \(f(x)=0\) has a root in \(R\). For example, if it is known that a continuous function \(f\) on \(R\) is positive at some point and its minimum values is negative, then the equation \(f(x)=0\) has a root in \(R\).
Consider \(f(x)=k e^x-x\) for all real \(x\), where \(k\) is real constant.Question:
The positive value of \(k\) for which \(k e^x-x=0\) has only one root is

If \(I_n=\int_{-\pi}^\pi \frac{\sin n x}{\left(1+\pi^x\right) \sin x} d x ; n=0,1,2\), \(\ldots\), then

The major product of the following reaction is

A solution is prepared by mixing $0.01\mathrm{mol}$ each of ${\mathrm{H}}_2{\mathrm{CO}}_3,{\mathrm{NaHCO}}_3,{\mathrm{Na}}_2{\mathrm{CO}}_3$, and $\mathrm{NaOH}$ in \(100 \mathrm{~mL}\) of water. $\mathrm{pH}$ of the resulting solution is
[Given: ${\mathrm{pK}}_{{\mathrm{a}}_1}$ and ${\mathrm{pK}}_{{\mathrm{a}}_2}$ of ${\mathrm{H}}_2{\mathrm{CO}}_3$ are $6.37$ and $10.32$, respectively. $\log 2=0.30$]

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Consider the circle \(x^2+y^2=9\) and the parabola \(y^2=8 x\). They intersect at \(P\) and \(Q\) in the first and the fourth quadrants, respectively. Tangents to the circle at \(P\) and \(Q\) intersect the \(\mathrm{X}\)-axis at \(R\) and tangents to the parabola at \(P\) and \(Q\) intersect the \(\mathrm{X}\)-axis at \(S\).Question:
The ratio of the areas of the \(\triangle P Q S\) and \(\triangle P Q R\) is