A ball is dropped from a height of 20 m. Time to reach ground (g=10) is MCQ with Answer and Explanation

Explanation:
Polarized sunglasses use polarizing filters to block horizontally polarized glare reflected from surfaces (water, roads). LCD displays use liquid crystals to rotate polarization, controlling light transmission through polarizers. Memory tip: 'Polarization applications: glare reduction (sunglasses), display technology (LCDs), 3D movies'. This application question tests wave optics uses, frequently appearing in competitive exams. Always link physical principles to everyday technologies; competitive exams emphasize practical relevance of physics concepts, making abstract phenomena tangible through common devices.

Explanation:
Surface tension = force/length. Force dimensions [MLT⁻²], length [L], so [MLT⁻²]/[L] = [MT⁻²]. Also energy per area gives same dimensions: [ML²T⁻²]/[L²] = [MT⁻²].

Explanation:
R = V²/P = 48400/100 = 484 Ω.