问题
问答题
某同学用伏安法测一段导体的电阻，其实验方案与
操作过程均正确，两表示数如图所示，你认为这个实验可以改进的地方是______这样做的理由是______．
答案
图示中电压表的示数偏小，在小量程的范围内，为了减小测量误差，使读数更加准确，电压表应改用小量程．
故答案为：电压表改用小量程；减小测量时的误差．
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某同学用伏安法测一段导体的电阻，其实验方案与
操作过程均正确，两表示数如图所示，你认为这个实验可以改进的地方是______这样做的理由是______．
图示中电压表的示数偏小，在小量程的范围内，为了减小测量误差，使读数更加准确，电压表应改用小量程．
故答案为：电压表改用小量程；减小测量时的误差．
| With 2005 fast becoming "the year of the natural disaster", it is time to reflect on how engineering, science and technology can play their fullest part in protecting the planet. Long before the Asian tsunami struck, the science community predicted the particular region of Indonesia to be hit by the next big earthquake; and the engineering and technology community had developed early warning systems costing only ＄ 30 million. But no government in the region heeded the warnings and no early warning systems were in place. We ignored technology of the advance warnings at our peril of 100,000 victims of the tsunami. Governments are not alone in ignoring the views of their scientific community; the public too has its doubts. Part of the reason for this lack of confidence must be down to the failure to engage them in a meaningful way about their concerns. Trust is a two-way street. Instead of claiming that everything would be rosy in the scientific garden "if only the public understood", we must work hard to explore concerns, discover fears and delve deep into the depths of public perceptions. We are getting there. There is a growing realization that effective public engagement is of far greater value than banging the "public understanding" drum. There are still doubters, of course, and sadly their cause is helped whenever they come across opinions presented as fact. All of us must guard against this debilitating practice. In time, effective public engagement should help deliver improved trust as well as better policy, which -- in turn -- might make it more difficult for scientists’ warnings to be ignored. Today’s technology community is a triumph of international collaboration where engineers and scientists combine to develop solutions to our biggest problems. Of course, technology cannot stop natural disasters but it can mitigate their impact. We are able to identify the birds affected by avian flu. We can chart their migration patterns around the world. We have the means to pursue vaccines. And we have the communication channels to keep people informed. Extolling the virtues of technology is not to pretend technology is perfect in every regard. Far from it. The profligate and unsustainable use of technology in energy and transport has contributed to climate change. But that doesn’t mean technology has failed us. We must never lose sight of the fact that technology itself will deliver the solutions to the very problems it can create. If we do, technology will remain sidelined and undervalued, and this major social failure will progressively disadvantage us all. Our vision is of a society embracing technology as a weapon of both progress and defense. Since the beginning of civilization, we have relied on it and enjoyed its benefits -- and most new technologies have had hugely beneficial effects for most people. But now, in an age when the death toll from natural disasters is increasing year on year, with more people living in danger zones, it is ever more urgent that we rely on science and technology to warn us of the dangers to come and provide the solutions we need. |
Which of the following is the idea stressed in the last paragraph
A．Technology is a weapon of both progress and defense.
B．People have relied on technology and enjoyed its benefits.
C．Natural disasters are increasing year by year.
D．It is science and technology that we rely on to predict dangers to come and provide solutions needed.