Consider a particle of mass m moving in one dimensional potential V(x)=x4 – 2x2. The phase trajectory (x,p) of the particle is best represented by

Phase trajectories are the constant-energy curves \(\frac{p^2}{2m}+V(x)=E\), so their shape is fixed by the extrema of V(x).
\(V'(x)=4x^3-4x=4x(x^2-1)=0\) gives x = 0 and x = ±1. Since V(0) = 0 is a local maximum and V(±1) = –1 are minima, this is a symmetric double-well potential.
The minima (±1, 0) are stable equilibria (centres): for –1 < E < 0 the particle is trapped in one well, giving two separate families of closed orbits around x = +1 and x = –1.
The maximum (0, 0) is an unstable equilibrium (saddle point). The E = 0 curve, p = ±√(2m(2x² – x⁴)), is the separatrix – a figure-of-eight passing through the origin and enclosing both wells.
For E > 0 the trajectories are large curves enclosing both wells outside the separatrix. The portrait with two centres, a saddle at the origin and a separatrix is the one that matches; portraits made of concentric closed curves around a single centre describe a single-well (harmonic-type) potential, and straight lines crossing at the origin describe only an inverted-oscillator saddle.
Hence, the answer is Phase portrait (B) — refer to the image in the original question.
The value of the line integral \(I = \int \vec{A}\cdot d\vec{r}\), where \(\vec{r} = x\hat{i} + y\hat{j}\) and \(\vec{A} = (x+y)\hat{i} + (y-x)\hat{j}\), along the path \(y^{2} = x\) from the point \((1, 1)\) to the point \((4, 2)\) is:
A set \(V\) of complex numbers forms a two-dimensional real vector space under the usual addition of complex numbers and multiplication by real numbers. Let \(T : V \to V\) be a linear transformation defined as \(T(z) = \bar{z}\). Eigenvalues of \(T\) are:
It is given that the residue of the complex function \(\dfrac{e^{1/z}}{z^{n}}\) at an isolated singular point \(z = 0\) is \(\dfrac{1}{9!}\). The value of \(n\) must be equal to:
The Cauchy principal value of the integral \(\displaystyle\int_{-\infty}^{\infty} \dfrac{e^{2ix}\sin x}{x}\,dx\) is:
The function \(f(x) = \exp(2x)\sin(2x)\) can be expanded as the Taylor series:
The inverse Laplace transform of \(\dfrac{2s^{2}}{s^{4}+5s^{2}+4}\) is:
Consider the differential operator \(L=a\dfrac{d^{3}}{dx^{3}}+b\dfrac{d^{2}}{dx^{2}}+c\dfrac{d}{dx}\) acting on the space of functions \(\{u_{i}(x)\mid 1\le x\le 2\}\) satisfying the boundary conditions \(u_{i}(1)=0=u_{i}(2)\). If \(L=L^{\dagger}\), then:
A general solution of the partial differential equation \(\dfrac{\partial^{2} f(x, y)}{\partial x^{2}} - \dfrac{\partial^{2} f(x, y)}{\partial y^{2}} = 0\) can be expressed in terms of arbitrary functions \(u\) and \(v\) as:
The Wronskian of two solutions of the differential equation \(x^{4}\dfrac{d^{2}y(x)}{dx^{2}}-2x^{3}\dfrac{dy(x)}{dx}-x^{8}y(x)=0\) is (up to a multiplicative constant):
Let \(T\) be any \(2 \times 2\) matrix with eigenvalues \(-1, 3\). For each positive integer \(n\), the numbers \(a_n\) and \(b_n\) are such that \(T^{\,n+1} = a_n T + b_n I\), where \(I\) is the \(2 \times 2\) identity matrix. Then \(a_n\) and \(b_n\) satisfy the recurrence relations:
.................... is a client server application that identifies each host on the internet with a unique user-friendly name.
Every OS has a ................ or .......... which primarily resides in the main memory of the computer to perform some of the basic functions of the OS.
(i) Kernel
(ii) Interface
(iii) Nucleus
(iv) Compiler
Codes:
Which of the following are referred to as low level language?
(i) Machine language
(ii) Assembly language
(iii) High level language
(iv) Natural language
Codes:
Match the following:
| List I | List II |
| (a) New York Public Library | (i) Shelv AR |
| (b) Miami University Augmented Research Group | (ii) Smart library |
| (c) Oula University Library | (iii) Wolf Walk |
| (d) North Carolina State University | (iv) Find the future |
Codes:
Which part of the QR code represents the encoded data?