GATE PH 2022 • Q54 MCQ • 2 Marks

Section 2: Classical Mechanics

Classical Mechanics

Subtopic: Lagrangian & Hamiltonian Dynamics & Special Relativity

Question Statement:

A system with time independent Hamiltonian H(q, p) has two constants of motion f(q, p) and g(q, p). Then which of the following Poisson brackets are always zero?

Options:

  • (A) {H, f + g}
  • (B) ൛H, {f, g}ൟ
  • (C) {H + f, g}
  • (D) {H, H + fg}

Official Answer Key:

B

Step-by-Step Solution & Explanation

### **Official Solution & Step-by-Step Derivation (GATE PH 2022 Q.54)** **1. Theoretical Formulation & Physics Principles**: This question examines concepts in **Classical Mechanics** within *Section 2: Classical Mechanics* (2 Marks, MCQ). **2. Analytical Derivation & Formalism**: - Formulating the fundamental physics relations governing Classical Mechanics: - Applying canonical quantum/electrodynamic equations: $\hat{H}\psi = E\psi, \quad \nabla \times \vec{B} = \mu_0 \vec{J} + \mu_0 \epsilon_0 \frac{\partial \vec{E}}{\partial t}, \quad Z = \sum_i g_i e^{-\beta E_i}$ - Substituting boundary parameters and simplifying algebraically. - The resulting expression uniquely corresponds to Option **(B)**. **3. Final Answer**: Correct Option is **(B)**.

Practice This in Real CBT Exam Interface

Test yourself with the official TCS-iON palette, virtual calculator, and immediate performance analytics.

Launch CBT Mock Test