Question

一道英文版的物理题，求解答，大致图形如下。（题目来自新加坡某中学的物理提纲）

The diagram below shows a solar heating system.

（a）Write down the process by which energy is transferred,
1)From the sun to the pipe.
2)From the pipe to the water flowing in the pipe.
(b)The material used to make the pipe is copper.Give reasons why copper is used and why the network of pipes is painted black.

Answer 1

a1 Radiation 热辐射
a2 Conduction 热传导

b Copper, as a metal, has very high heat conductivity, and very low heat capacity. Therefore heat can be transferred to the water very fast, and the pipe system itself does not absorb too much. To pint them black is to decrease the outward heat radiation.
铜，作为一种金属，有很强的导热性和很低的热容量。因而热量可以很快的传给水，而管道本身却不吸收很多。把它涂黑是为了减少向外界热辐射。