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Author Question: On sunny days, why do hot-air balloons suddenly rise when they drift over a wide road or a black ... (Read 83 times)

debasdf

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on: Jul 29, 2018
On sunny days, why do hot-air balloons suddenly rise when they drift over a wide road or a black asphalt parking lot?
 
  What will be an ideal response?

Question 2

In one word, account for water temperature exceeding 100C in the power plant of a nuclear submarine.
 
  A) conductivity
  B) evaporation
  C) condensation
  D) pressure
  E) vaporization


amandanbreshears

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Reply #1 on: Jul 29, 2018
Answer to Question 1

Answer: Air over a warm surface is warmed, becomes less dense, and is buoyed upward. That is why air warmed by a hot black surface rises. Hence a balloon is carried upward by the rising air.

Answer to Question 2

Answer: D


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