The weight of a body at Earth's centre is MCQ with Answer and Explanation

Explanation:
An isochoric process is a thermodynamic process in which the volume of the closed system remains constant (delta V = 0). Because there is no change in volume, the system does zero pressure-volume work (W = Pdelta V = 0). According to the first law of thermodynamics, any heat added goes entirely into increasing the internal energy. Isobaric is constant pressure; isothermal is constant temperature.

Explanation:
Polarization (restriction of electric field oscillation to one plane) is possible only for transverse waves, where oscillations are perpendicular to propagation direction. Longitudinal waves (e.g., sound) cannot be polarized as oscillations are along propagation. This was key evidence for light's transverse wave nature. Memory aid: 'Polarization ⇒ transverse wave; light is EM transverse wave'. This conceptual question tests wave optics fundamentals, frequently examined in competitive exams. Always distinguish wave types: transverse (light, string waves) vs longitudinal (sound, spring waves).

Explanation:
v_e = √(2GM/R): depends on planet's M and R, independent of projectile mass or launch direction. Memory tip: 'v_e ∝ √(M/R); property of planet, not projectile'. Gravitation concept frequently tested in competitive exams.