答案(点此获取答案解析)
1kg\u7684\u6c34\u6e29\u5ea6\u5347\u9ad8\uff08\u964d\u4f4e\uff091\u2103\uff0c\u5438\u6536\uff08\u653e\u51fa\uff09\u7684\u70ed\u91cf\u662f4.2\u00d7103J,1kg\u7684\u65e0\u70df\u7164\u5b8c\u5168\u71c3\u70e7\uff0c\u653e\u51fa\u7684\u70ed\u91cf\u