A thin copper wire at 300° is suddenly immersed in water at 30°C. It cools down to 150°C in 70 seconds. It is then reheated to the initial temperature of 300°C and suddenly exposed to air at 30°C where it cools down to 150°C in 200 seconds. This difference in cooling time is due to

Smaller heat transfer coefficient of water

Larger heat transfer coefficient of water

A thin copper wire at 300° is suddenly immersed in water at 30°C. It

1.	A thin copper wire at 300° is suddenly immersed in water at 30°C. It cools down to 150°C in 70 seconds. It is then reheated to the initial temperature of 300°C and suddenly exposed to air at 30°C where it cools down to 150°C in 200 seconds. This difference in cooling time is due to
A.	Larger specific heat of water
B.	Larger heat transfer coefficient of water
C.	Smaller heat transfer coefficient of water
D.	None of the above
Answer» C. Smaller heat transfer coefficient of water

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A thin copper wire at 300° is suddenly immersed in water at 30°C. It cools down to 150°C in 70 seconds. It is then reheated to the initial temperature of 300°C and suddenly exposed to air at 30°C where it cools down to 150°C in 200 seconds. This difference in cooling time is due to

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