(10分)传送带设备种类繁多,主要有带式输送机、板式输送机、小车式输送机、自动扶

题型:计算题

问题:

(10分)传送带设备种类繁多,主要有带式输送机、板式输送机、小车式输送机、自动扶梯、自动人行道、刮板输送机、埋刮板输送机、斗式输送机、斗式提升机、悬挂输送机和架空索道。下图为一平直的带式输送机以速度v=2m/s匀速运动,输送机负责把A处的工件运送到B处,A、B相距L=12m。从A处释放的工件初速度为零,求:

(1)若工件经时间t=8s能传送到B处,求工件做匀加速运动所用的时间;

(2)欲用最短时间把工件从A处传到B处,求输送机的运行速度至少多大。(结果保留三位有效数字)

考点:匀变速直线运动
题型:计算题

成角透视图中的家具位置可以从平面图中相应的格子所在位置搬过来。( )

题型:计算题

根据短文内容,从短文后的选项中选入能填入空白处的最佳选项。选项中有两项为多余选项。

If you want to keep fit, please refer to the following:

Move More

Make it a daily to find ways to move your body.  小题1:Climb stairs instead of taking the elevator(电梯). Walk your dog; play with your kids. It doesn’t have to be an hour in the gym or a 45-minute dance class. But that’s great when you’re up to it. At the same time, move more.

Give up Smoking

Ever since 1960 when it was announced that smoking was harmful to health, Americans have been reducing their use of tobacco products. Just recently, we’ve seen more and more teens smoking. Could it be the Hollywood influence?  小题2:  Take care! Warn your children against smoking.

小题3:  

While recent studies show a glass of wine or one drink a day can help protect against heart disease, more than that can cause other health problems such as liver and kidney(肝肾) disease and cancer.

Reduce Stress(压力)

Easier said than done, stress comes in many ways.  小题4:  Spend 30 minutes a day doing something you like such as walk on the beach or in a park, read a good book, visit a friend, listen to relaxing music, and watch a funny movie.

Protect Yourself from Pollution

If you can’t live in a smog-free environment, at least avoid smoke-filled rooms. 小题5:  Exercise indoors in air conditioning when air quality is good.

A.Avoid Excessive(过量的) Drinking

B.There are many things you can do to move your arms and legs.

C.Think carefully about what you will do.

D.Exercise outside when the smog rating is low.E. It seems that the stars in every movie smoke cigarettes.

F. Keep a Positive Mental Outlook

G. Some techniques given by experts are to think positive thoughts.

题型:计算题

中 * * 党十七大报告指出,社会安定的重要保证是

A.社会保障

B.社会保险

C.社会救助

D.社会福利

题型:计算题

能平补气阴的药是:

A.党参

B.山药

C.白术

D.甘草

E.菟丝子

题型:计算题

与等额本息还款法比较而言,等额本金还款法( )。

A.在还款初期高于等额本息还款法

B.贷款门槛要高于等额本息还款法

C.对于经济尚未稳定而且是初次贷款购房的人来说是有利的

D.等额本金还款法的还本速度比较快,风险比等额本息还款法小

E.在最初贷款购买房屋时,负担比等额本息还款法重

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