A student measures length as 3.600 cm using vernier calliper of least count 0.001 cm. Number of significant figures is MCQ with Answer and Explanation

Explanation:
Magnetic field intensity (H) and magnetic field (B) are vectors. Magnetic flux is scalar (Φ = B·A). Resistance scalar, potential scalar. Vector quantities have direction. Current has direction but adds by scalar law, considered tensor sometimes but in basic physics not vector.

Explanation:
A lactometer is a specific type of hydrometer used to test the purity of milk by measuring its relative density. All hydrometers, including lactometers, work on Archimedes' Principle of buoyancy. They float at a depth that depends directly on the density of the liquid; they sink deeper in less dense liquids (like milk heavily diluted with water).

Explanation:
Mass m = 20 g = 0.02 kg. Momentum p = m v = 0.02 × 200 = 4 kg m/s. Always convert mass to kg. Momentum unit kg·m/s.