Free fall: height h takes time t. Height 4h takes time: MCQ with Answer and Explanation

Explanation:
Evaporation absorbs latent heat from surroundings, causing cooling.

Explanation:
Archimedes' principle: buoyant force = weight of displaced fluid. Law of floatation: floating body displaces fluid equal to its own weight. Archimedes discovered it. Pascal gave pressure law.

Explanation:
Logic gates process digital signals. An AND gate acts like two switches in series. Current (a logic HIGH or 1) will only flow to the output if Switch A AND Switch B are closed (HIGH). The truth table for an AND gate shows output = 1 solely when Input A = 1 and Input B = 1. In all other combinations, the output is strictly 0.