搜题
网友您好,请在下方输入框内输入要搜索的题目:
搜题
题目内容 (请给出正确答案)
提问人:网友Rockay_liu 发布时间:2022-01-07
[主观题]

the switch in the circuit shown has been closed for a long time and is opened at t=0. find

the switch in the circuit shown has been closed for a long time and is opened at t=0. Find: a) the initial value of v(t). b) the time constant for t>0. c) the numerical expression for v(t) after the switch has been opened. d) the initial energy stored in the capacitor.the switch in the circuit shown has been closed fo

简答题官方参考答案 (由简答题聘请的专业题库老师提供的解答)
  抱歉!暂无答案,正在努力更新中……
更多“the switch in the circuit shown has been closed for a long time and is opened at t=0. find”相关的问题
第1题
The outcome of the crisis will be more serious for Iran and Venezuela.
点击查看答案
第2题
—?Have you moved to your new house??— Not yet. My ...
— Have you moved to your new house?

— Not yet. My house _____.

[    ]

A. has been painted

B. is painted

C. is painting

D. is being painted

点击查看答案
第3题
. Complete the sentences with the verbs below in the correct form. make borrow earn save lose spend lend win 1 My daughter worked part-time after school to enough money to take a gap year. 2 Many people a lot of money when the stock market crashed. 3 The company a large amount of money on public relations after the scandal. 4 If you buy in bulk, you can money. 5 How much interest are you paying on the money the bank you?
点击查看答案
第4题
What are the two aspects of health and safety? Please explain and answer in details?
点击查看答案
第5题
阅读理解。????Environmentalists said our planet was...
阅读理解。
Environmentalists said our planet was doomed to die. Now one man says they are wrong.

"Everyone knows the planet is in bad shape," thundered a magazine article last year. Species are being

driven to die out at record rates, and the rivers are so poisonous that fish are floating on the surface, dead.

But there's a growing belief that what everyone takes for granted is wrong: things are actually getting

better. A new book is about to overturn our most basic assumptions about the world's environment. Rivers, seas, rain and the atmosphere are all getting cleaner. The total amount of forests in the world is not

declining. The Skeptical Environmentalist by Bjorn Lomborg, professor of statistics at the University of

Aarhus in Denmark, is an attack on the misleading claims of environmental groups, and the "bad news"

culture that makes people believe everything is getting worse.

Now the attacks are increasingly coming from left-wing environmentalists such as Lomborg, a former

member of Greenpeace. The accusation is that, although the environment is improving, green groups-with

profits of hundreds of mil-lions of pounds a year - are using scare tactics(谋略)to gain donations. Lomborg's book doesn't deny global warming - probably the biggest environmental threat - but destroys almost

every other environmental claim with many official statistics.

The Worldwatch Institute claims that "deforestation(沙漠化) has been accelerating over the last 30

years". But Lomborg says that is simply rubbish. Since the dawn of agriculture the world has lost about

20 per cent of its forest cover, but in recent decades the forest area'sdepletinghas come to a stop.

According to UN figures, the area of forests has remained almost steady, at about 30 per cent of total

land area, since the 1940s. Forests in countries such as the US, the UK and Canada have actually been

expanding over the past 40 years. Despite all the warnings the Amazon rainforest has only shrunk by

about 15 per cent.

Nor are all our species dying out. Some campaigners claim that 50 per cent of all species will have

died out within 50 years. But other studies show only 0.08 per cent of species are dying out each year.

Conservation efforts have been successful. Whales are no longer threatened and the bald eagle is off the

endangered list.

Environmental groups claim that many of the improvements are the results of the success of their

campaigns. Stephen Tindale, director of Greenpeace UK, said, "There are important examples, such as

acid rain and ozone, where things aren't as bad as predicted, and that's because behavior has changed."

1. In his book,The Skeptical Environmentalist, what is Lomborg's main argument?
A. Our planet is in bad shape.

B. The world's environment is improving.

C. The total amount of forests in the world is not declining.

D. Conservation efforts have been successful.

2. What is Lomborg's main accusation of environmentalists?
A. They scared people into making donations.

B. They overturned our basic assumptions about the world's environment.

C. They changed their behavior toward the environment.

D. They only told people bad news about the environment.

3. The underlined word "depleting" in Paragraph 5 is closest in meaning to "____".
A. reducing

B. limiting

C. expanding

D. accelerating

4. According to the passage, which of the following statements is true?
A. The total area of forests in the world has increased significantly.

B. The effects of global warming are not as bad as first expected.

C. It appears that the bald eagle will now survive.

D. In the last 50 years the number of whales has increased.

点击查看答案
第6题
The switch in the circuit show in figure has bee in position a for a long time. At t=0 the switch is moved to position b. a) what is the initial of vC? b) what is the final vlaue of vC ? c) what is the time constant of the circuit when the switch is in position b ? d) what is the expression for vC(t) when t>0 ? e) what is the expression for i(t) when t>0 ? f) plot vC(t) and i(t) versus t.
点击查看答案
第7题
在由若干机器并联构成的机组中,若这些机器中单机效率相等均为η0,则机组的总效率η必有如下关系:     。

A、η>η0

B、η<η0<br> C、η=η0

D、(n为单机台数)

点击查看答案
第8题
轴颈1与轴承2组成转动副,细实线的圆为摩擦圆,轴颈1受到外力(驱动力)Q的作用,则轴颈1作    。

A、等速运动

B、加速运动

C、减速运动

D、静止不动

点击查看答案
重要提示: 请勿将账号共享给其他人使用,违者账号将被封禁!
查看《购买须知》>>>
重置密码
账号:
旧密码:
新密码:
确认密码:
确认修改
购买搜题卡查看答案
购买前请仔细阅读《购买须知》
请选择支付方式
微信支付
支付宝支付
点击支付即表示你同意并接受《服务协议》《购买须知》
立即支付
搜题卡使用说明

1. 搜题次数扣减规则:

功能 扣减规则
基础费
(查看答案)
加收费
(AI功能)
文字搜题、查看答案 1/每题 0/每次
语音搜题、查看答案 1/每题 2/每次
单题拍照识别、查看答案 1/每题 2/每次
整页拍照识别、查看答案 1/每题 5/每次

备注:网站、APP、小程序均支持文字搜题、查看答案;语音搜题、单题拍照识别、整页拍照识别仅APP、小程序支持。

2. 使用语音搜索、拍照搜索等AI功能需安装APP(或打开微信小程序)。

3. 搜题卡过期将作废,不支持退款,请在有效期内使用完毕。

请使用微信扫码支付(元)

订单号:

遇到问题请联系在线客服

请不要关闭本页面,支付完成后请点击【支付完成】按钮
遇到问题请联系在线客服
恭喜您,购买搜题卡成功 系统为您生成的账号密码如下:
重要提示:请勿将账号共享给其他人使用,违者账号将被封禁。
发送账号到微信 保存账号查看答案
怕账号密码记不住?建议关注微信公众号绑定微信,开通微信扫码登录功能
警告:系统检测到您的账号存在安全风险

为了保护您的账号安全,请在“简答题”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!

- 微信扫码关注简答题 -
警告:系统检测到您的账号存在安全风险
抱歉,您的账号因涉嫌违反简答题购买须知被冻结。您可在“简答题”微信公众号中的“官网服务”-“账号解封申请”申请解封,或联系客服
- 微信扫码关注简答题 -
请用微信扫码测试
欢迎分享答案

为鼓励登录用户提交答案,简答题每个月将会抽取一批参与作答的用户给予奖励,具体奖励活动请关注官方微信公众号:简答题

简答题官方微信公众号

简答题
下载APP
关注公众号
TOP