Which of the following statements is true/correct
  • A
    During clear nights, the temperature rises steadily upward near the ground level
  • B
    Newton's law of cooling, an approximate form of Stefan's law, is valid only for natural convection
  • C
    The total energy emitted by a black body per unit time per unit area is proportional to the square of its temperature in the Kelvin scale
  • DTwo spheres of the same material have radii $1m$ and ${S_1}$ and temperatures $4000 K$ and $2000 K$ respectively. The energy radiated per second by the first sphere is greater than that radiated per second by the second sphere
Medium
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