關於ｐｈｙ

1/空氣是不良的導體
有助減小外界的熱進入電櫃
從而有助保持食物格冰凍
2a/由於陽光能在玻璃窗進入車廂,但部分的光就不能出來,因為玻璃窗會把部分離開的光反射回車廂,原理就同溫室效應一樣,玻璃窗就是大氣層中的CO2
b/由於遮光板有助減小進入的陽光,使發生2a/的機會減少,從而減低車廂內溫度的升幅
遮光板是以反光的物料做成,原理是當陽光進入時如窗子一樣把光反射走,而且遮光板的顏色吸熱會較慢

1) As air is a poor conductor of heat, the layer of air between the two walls of the fridge helps preventing heat gain by conduction.

2)
a) There are great heat gain by radiation from the light energy of th sun,however,there are no or less heat loss by convection and conduction,as the material making the interior area of the car is not a good radiation emitor,so the heat loss by radiation is also poor.As a result, there are net heat gain by radiation.So that the temp. of the car increase.

b)This sheet used shining material as the outer layer(ie.Aluminium) so that it can prevent heat gain by radiation by means of reflecting the sun light.