Torque dimensions same as: MCQ with Answer and Explanation

Explanation:
Bohr model: r_n = n²a₀ ⇒ r ∝ n². Higher n = larger orbit. Memory tip: 'Bohr: r ∝ n²; E ∝ -1/n²'. Atomic physics relation frequently tested in competitive exams.

Explanation:
Sound requires material medium for mechanical wave propagation. Vacuum lacks particles to transmit vibrations. Light (EM wave) travels through vacuum. Memory tip: 'Sound = mechanical wave ⇒ needs medium; light = EM wave ⇒ no medium needed'. Fundamental wave property frequently tested in competitive exams to assess medium-dependence understanding.

Explanation:
From kinetic theory, rms speed v_rms = √(3RT/M), where R is gas constant, T absolute temperature, M molar mass. Thus v_rms ∝ √T. This shows molecular speed increases with temperature but not linearly. Memory aid: 'Kinetic energy ∝ T; KE = ½mv² ⇒ v ∝ √T'. This conceptual question tests kinetic theory understanding, frequently examined in thermodynamics sections of competitive exams. Always use absolute temperature (Kelvin) in gas law calculations; Celsius would give incorrect proportionality.