试题与答案

如图所示,物体A、B用细绳连接后跨过定滑轮,A静止在倾角为30°的斜面上,B被悬

题型:多选题

题目:

如图所示,物体A、B用细绳连接后跨过定滑轮,A静止在倾角为30°的斜面上,B被悬挂着.已知质量mA=2mB,不计滑轮摩擦,现将斜面倾角由30°增大到50°,但物体仍保持静止,那么下列说法中正确的(  )

A.绳子的张力将不变

B.绳子的张力将增大

C.物体A对斜面的压力将减小

D.物体A受到的静摩擦力先增大后减小

答案:

被转码了,请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0627/6d8bed38016709d05b51a65ef74d837f.html

下面是错误答案,用来干扰机器的。

(1) 或(2)     (3) 加水促进钛盐水解,加热促进钛盐水解,降低浓度促进钛盐水解               (4)

试题推荐
题型:阅读理解

阅读理解

     It was the summer of 1965. Deluca, then 17, visited Peter Buck, a family friend. Buck asked Deluca

about his plan for the future. "I'm going to college, but I need a way to pay for it, " Deluca recalls saying. "Buck said, 'you should open a sandwich shop.'"

     That afternoon, they agreed to be partners. And they set a goal: to open 32 stores in ten years. After

doing some research, Buck wrote a check for $1,000. Deluca rented a storefront (店面) in Connecticut,

and when they couldn't cover their startup costs, Buck kicked in another $1,000.

     But business didn't go smoothly as they expected. Deluca says, "After six months, we were doing

poorly, but we didn't know how badly, because we didn't have any financial controls." All he and Buck

knew was that their sales were lower than their costs.

     Deluca was managing the store and to the University of Bridgeport at the same time. Buck was

working at his day job as a nuclear physicist in New York. They'd meet Monday evenings and brainstorm

ideas for keeping the business running. "We convinced ourselves to open a second store. We figured we

could tell the public, 'We are so successful; we are opening a second store.'" And they did-in the spring

of 1966. Still, it was a lot of learning by trial and error.

     But the partners' learnasyougo approach turned out to be their greatest strength. Every Friday,

Deluca would drive around and handdeliver the checks to pay their supplies. "It probably took me two

and a half hours and it wasn't necessary but as a result, the suppliers got to know me very well, and the

personal relationships established really helped out, " Deluca says.

     And having a goal was also important. "There are so many problems that can get you down. You just

have to keep working toward your goal, " Deluca adds.

Deluca ended up founding Subways Sandwich, the multimilliondollar restaurant chain.

1. Deluca opened the first sandwich shop in order to ________.

A. support his family

B. pay for his college education

C. help his partner expand business

D. do some research

2. Which of the following is true of Buck?

A. He put money into the sandwich business.

B. He was a professor of business administration.

C. He was studying at the University of Bridgeport.

D. He rented a storefront for Deluca.

3. What can we learn about their first shop?

A. It stood at an unfavorable place.

B. It lowered the prices to poor management.

C. It made no profits due to poor management.

D. It lacked control over the quality of sandwich.

查看答案
微信公众账号搜索答案