MCQ
When fluids are heated from the bottom, convection currents are produced because
  • A
    Molecular motion of fluid becomes aligned
  • B
    Molecular collisions take place within the fluid
  • C
    Heated fluid becomes more dense than the cold fluid above it
  • Heated fluid becomes less dense than the cold fluid above it

Answer

Correct option: D.
Heated fluid becomes less dense than the cold fluid above it
(d)

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