问题 填空题

俗话说“小小秤砣压千斤”,这可以根据___________________来解释.只要秤砣对秤杆作用的力臂比所挂物对秤杆作用的力臂___________(选填“大得多”或“小得多”),那么“小小秤砣压千斤”是完全可以实现的。

答案

杠杆平衡条件(或“杠杆原理”) 大得多

秤杆在使用时秤砣与物体可看做动力与阻力,根据杠杆平衡的条件:F1l1=F2l2,当动力臂远大于阻力臂时用较小的动力就能使秤杆平衡,达到“小小秤砣压千斤”的效果.

故答案:大得多

阅读理解

Twelve years ago, a young traveler named Rhett Butler from San Francisco, California, visited the Sabah rainforest on Malaysian Borneo. In one area of the rainforest, he watched a bird flying through the trees. The beautiful sight left quite an impression on him. But weeks later, back home, Rhett Butler got the news that trees had been cut down in the area he visited.

To keep his website going, he travels around the world on several major trips each year. His working tools are a laptop computer, cameras and sometimes diving equipment. He often calls on experts for information. For example, he interviewed Alison Jolly, a top experts on lemurs(狐猴). He interviewed Rodney Jackson, a biologist who established the Snow Leopard Conservancy.

Stories like these have made Mongabay a favorite place on the Internet for researchers, students and teachers. In April, Time.Com named it one of the fifteen top climate and environment websites in the world.

小题1: What’s the main idea of the passage?

A.Rhett Butler and his website.

B.Rainforest on Malaysian Borneo.

C.How Rhett Butler protected rare animals.

D.How Rhett Butler made his website popular.小题2:Rhett Butler didn’t publish his book about rainforests because _______.

A.making websites earns more money than writing books

B.he didn’t want to become a writer

C.the book was not about rainforest protection

D.he wanted to use the information to create a website小题3:Which of the followings is NOT true about the Mongabay. Com?

A.It was set up in 1999.

B.It attracted many advertisers.

C.At least two related websites grew from it.

D.Rhett Butler made a lot of money from it.小题4:To keep his website going, Rhett Butler ________.

A.kept visiting the rainforest

B.traveled around and interviewed experts

C.raised rare snow leopards

D.made a great number of advertisements小题5:We can learn from the passage that _________.

A.Mongabay.Com was loved by researchers as well as students

B.kids. Mongabay.Com. has many stories written by kids

C.WildMadagascar.org is better known than Mongabay.Com

D.Rodney Jackson was once a businessman

多项选择题