冬天,双手捧着热水袋会感到暖和,双手反复摩擦也会感到暖和,前者是利用___________方式增加了手的内能,后者是利用___________方式增加了手的内能。
热传递 做功
用所给动词的适当形式填空。
1. He is going to ______ (watch) TV this Sunday.
2. Why don't you ______ ( go) to movies?
3. We should ______ (study) hard.
4. It's a good idea ______ (read ) English in the morning.
5. How about ______ (play) football this afternoon?
6.—What aer they doing?
—They ______ (listen) ot music.
7. Can you ______ (help ) me with my English?
8. How often write the correct ______ (spell )next to the mistakes.
用质量相等的O℃的水和O℃的冰来冷却物体,______的冷却效果较好.原因是______.