Emperor penguins are warm blooded animals. They live in the South pole and can withstand very low temperature.
(a) State two features of the Emperor penguins which provide excellent insulation to keep them warm in extreme cold weather. Explain briefly. (5 marks)
(b) Emperor penguins cooperate to face freezing winds blow off the South pole. To keep warm, they crowd together in a small space to share their warmth. Explain why this action could reduce energy lost to the surrounding. (3 marks)
i'm not sure about the answer...-_-
thank you.
phy question (heat transfer)
2010-02-18 12:28 am
回答 (2)
2010-02-18 2:22 am
✔ 最佳答案
a. The Emperor penguins have thick fur on their body. As the fur is a good insulator of heat, this can reduce heat loss by conduction.Also, the back of the penguin is black in colour, this is to maximize the radiation absorbed to their body to increase heat transfer to the body by radiation.
b. This action can greatly reduce the total surface area exposed to the cold surrounding and hence reduce heat lost.
參考: Physics king
2010-02-18 5:02 am
(a) The two insulation features of an Emperor penduin are:
(i) overlapping densely packed feathers make a surface almost impenetrable to wind and water. The trapped air in feathers provide 80% to 84% of the thermal insulation to penguins.
(ii) a layer of under-skin fat. This layer of fat improves insulation when the penguin swims in cold water.
(b) By huddling in a group of hundreds or even thousands, most of the penguins have another warm penguin blanket to shield them instead. The surface area of the group is greatly reduced and a great deal of warmth and body fat conserved. By a continual movement of penguins from the outside of the group to the centre, so displacing the warmer and more protected penguins to the outside, such that eah penguin will take its turn in the worst places against the wind and raw cold.
The following web-page gives a very good account on how penguins keep themselves warm against the cold Antactic weather,
http://www.coolantarctica.com/Antarctica%20fact%20file/science/cold_penguins.htm
(i) overlapping densely packed feathers make a surface almost impenetrable to wind and water. The trapped air in feathers provide 80% to 84% of the thermal insulation to penguins.
(ii) a layer of under-skin fat. This layer of fat improves insulation when the penguin swims in cold water.
(b) By huddling in a group of hundreds or even thousands, most of the penguins have another warm penguin blanket to shield them instead. The surface area of the group is greatly reduced and a great deal of warmth and body fat conserved. By a continual movement of penguins from the outside of the group to the centre, so displacing the warmer and more protected penguins to the outside, such that eah penguin will take its turn in the worst places against the wind and raw cold.
The following web-page gives a very good account on how penguins keep themselves warm against the cold Antactic weather,
http://www.coolantarctica.com/Antarctica%20fact%20file/science/cold_penguins.htm
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