题干

认识自然,亲近自然,学校组织学生到桐洲岛进行社会实践活动,小明携带一个质量为1Kg的合金锅、一台如图所示的便携式丁烷气炉(内置一瓶新的燃气,参数如表格所示),爱探究的小明通过手机上网查到便携式燃气炉的热效率为30%,丁烷气体的燃烧效率为90%,野炊地水的沸点为100℃,测出当地水的温度为20℃,[水的比热容为 4.2×103J/(kg⋅°C) ,锅的比热容为 0.8×103J/(kg⋅°C) ]

品名
便携式丁烷气炉
质量
1.88Kg(不含气瓶)
型号
WZL-168-A
尺寸
343*284*113mm
用途
野外用
点火方式
电子点火
使用燃气
液化丁烷气
燃气消耗量
150g/h(最大火力时)

气瓶规格(尺寸/容量)
品名
总质量
净质量
主要成分
热值
神州
354g
250g
丁烷
9×107J/kg
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    MOOCs (Massive Open Online Courses) are free, but without tutoring, and are open to anyone, anywhere in the world. The courses are flexible — normally three to five hours of study a week — done at any time, short (5 to 10 weeks) and video-rich. They are also heavily dependent on crowd sourcing: you can discuss a course with fellow students through online forums, discussion boards and peer review. Students don't have to finish the courses, pass assessments or do assignments, but, if they do, they get a certification of participation.

    The Open University launched FutureLearn, the UK's answer to US platforms such as Coursera, EdX and Udacity, which have been offering MOOCs from top US universities for the past two years. The response has been incredible, with more than three million people registering worldwide. Meanwhile, in 2012, Edinburgh University became the first non-US institution to join Coursera's partnership, comprising 13 universities. “We already run 50 online master's degrees, so this was a logical expansion,” says Professor Jeff Haywood, Edinburgh's vice-principal. “It's an investment in teaching methods research. How am I going to teach introductory philosophy to 100,000 people? That's what I call educational R&D.” He adds “If you look ahead 10 years, you'd expect all students graduating to have taken some online courses, so you've got to research that. Our MOOCs are no more in competition with our degrees than a lifelong learning course because they don't carry credits.”

    Cooperation is key, Haywood stresses. It is far better to offer 20-30 courses in your own areas of expertise (专门技能) and let other institutions do likewise. Professor Mike Sharples, FutureLearn's academic lead, goes further: “We've tied the elements available before into a package of courses offered by leading universities worldwide on a new software platform, with a new way of promoting it and also a new social-learning teaching method. You won't just receive an exam, but be able to discuss and mark each other's assignments.”

    Bath University, one of more than 20 universities working with FutureLearn, launches its first course, Inside Cancer, next January, and regards MOOCs as a way of breaking down age barriers. “There's no reason why someone doing GCSEs should not look at our MOOCs and get quite a way through them, or someone at PhD level and beyond,” says Professor Bernie Morley, expert for learning and teaching.