Questions

Maglev trains are used in Japan, South Korea and China only.

Maglev derived from magnetic levitation using the principle of magnetic repulsion is a system of train transportation that uses two sets of magnets, one set to repel and push the train up off the track as in levitation then another set to move the 'floating train' ahead at great speed taking advantage of no friction. Maglev trains are therefore quieter and smoother than conventional trains, and have the potential for much higher speeds

Despite over a century of research and development, maglev transport systems are in operation in just three countries Japan, South Korea and China.

Hence Maglev -- Magnetic-levitation.

The caste system in India divides Hindus into four main categories - Brahmins, Kshatriyas, Vaishyas and the Shudras. The main castes were further divided into about 3,000 castes and 25,000 sub-castes, each based on their specific occupation.

Lithoshpere are composed of rocks in the crust and upper mantle that behave as brittle solids. The lithosphere is Earth's outermost layer.

Kelvin is used to measure Temperature,

Candela is used to measure Intensity of flame,

Steredian is used to measure Solid Angle.