#1
2nd August 2014, 03:45 PM
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JEST (physics) old papers
Here I am looking for the JEST (physics) old papers, is there any buddy to provide me the same????????
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#2
3rd August 2014, 10:33 AM
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Re: JEST (physics) old papers
As per your request here I am sharing the JEST (physics) old paper: 1. Black-body radiation, at temperature Ti fills a volume V. The system expands adiabatically and reversibly to a volume 8V. The final temperature Tf = xTi, where the factor x is equal to (a) 0.5 (b) 2.8 (c) 0.25 (d) 1 2. A particle of mass m, constrained to move along the x-axis. The potential energy is given by, V(x)=a + bx +cx2, where a, b and c are positive constants. If the particle is disturbed slightly from its equilibrium position, then it follows that (a) it performs simple harmonic motion with period 2 pÖ(m/2c) (b) it performs simple harmonic motion with period 2 pÖ(ma/2b2) (c) it moves with constant velocity (d) it moves with constant acceleration 3. Consider a square ABCD, of side a, with charges +q, -q, +q, -q placed at the vertices, A, B, C, D respectively in a clockwise manner. The electrostatic potential at some point located at distances r (where r >> a) is proportional to (a) a constant (b) 1/r (c) 1/r2 (d) 1/r3 4. The general solution of dy/dx – y = 2ex is (C is an arbitrary constant) (a) e2x+Cex (b) 2xex+Cex (c) 2xex+C (d) ex2+C 5. As q®0, lim + q q sin ) sin 1 ln( is (a) ¥ (b) -¥ (c) 1 (d) 0 6. If P^ is the momentum operator, and s^ are the three Pauli spin matrices, the eigenvalues of (s^.P^) are (a) px and pz (b) px ± ipy (c) ± |p| (d) ± (px + py +pz) 7. Two parallel infinitely long wires separated by a distance D carry steady currents I1 and I2 (I1 > I2) flowing in the same direction. A positive point charge moves between the wires parallel to the currents with a speed v at a distance D/2 from either wire. The magnitude of an electric field that must be turned on to maintain the trajectory of the particle is proportional to (a) (I1-I2)v/D (b) (I1+I2)v/D (c) (I1-I2)v2/D2 (d) (I1+I2)v2/D2 8. An ideal gas of non-relativistic fermions in three dimensions is at a temperature of 0 K. When both the mass of the particles and the number density are doubled, the energy per particle is multiplied by a factor, (a) Ö2 (b) 1 (c) 21/3 (d) 1/21/3 9. The rotational part of the Hamiltonian of a diatomic molecule is (1/2 µ1)(Lx 2+Ly 2) + (1/2 µ2) Lz 2 where µ1 and µ2 are moments of inertia. If µ1 = 2µ2, the three lowest energy levels (in units of h2/4 µ2) are given by (a) 0, 2, 3 (b) 0, 1, 2 (c) 1, 2, 3 (d) 0, 2, 4 10. A particle of mass 1 gm starts from rest and moves under the action of a force of 30 Newtons defined in the rest frame. It will reach 99% the velocity of light in time (a) 9.9 x 103 sec (b) 7 x 104 sec (c) 0.999 sec (d) 0.7 sec |
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