Same chapter3 marksDifficulty: Medium
A Carnot engine works between 500 K and 300 K. Find its efficiency.
Heat and Thermodynamics
3 marksDifficulty: Medium
Distinguish between conduction, convection and radiation.
Original Khojo Papers practice question — not from a past board paper.
Answer
In conduction heat travels through a body from particle to particle without any bulk movement of matter, and it needs a medium. In convection heat is carried by the bulk movement of a heated fluid, so it too needs a medium and occurs only in fluids. In radiation heat travels as electromagnetic waves and needs no medium at all.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Heat from the sun reaches the earth by radiation alone.
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