A hydraulic press has area ratio 10:1. A force of 20 N on small piston can lift load of MCQ with Answer and Explanation

Explanation:
Atomic diameter ~ 1 Å = 10⁻¹⁰ m. Nucleus is 10⁻¹⁵ m (femtometre). Atomic size determined by electron cloud. 10⁻⁶ m is typical cell size. 10⁻³ m is millimetre.

Explanation:
p = m v = 5 × 2 = 10 kg m/s. Direction same as velocity. Momentum vector. Unit kg·m/s.

Explanation:
Total internal reflection (TIR) is exploited in optical fibers for light transmission with minimal loss (core-cladding interface). In diamonds, high refractive index (n≈2.4) gives small critical angle (~24°), so most light undergoes TIR, enhancing brilliance through multiple reflections. Memory aid: 'TIR applications: optical fibers (communication), diamonds (sparkle), prisms (binoculars)'. This application question tests optics uses, frequently appearing in competitive exams. Always link physical principles to technological applications; competitive exams emphasize practical relevance of theoretical concepts.