A lactometer is used to check MCQ with Answer and Explanation

Explanation:
Hydrogen bomb (thermonuclear weapon) uses uncontrolled nuclear fusion of hydrogen isotopes, triggered by a fission bomb. Releases enormous energy. Sun also uses fusion. Fission used in atomic bomb.

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.

Explanation:
v_esc ∝ √M. M'=9M => v'=3×11.2=33.6 km/s.