问题 选择题

一个置于水平粗糙桌面上的木块在拉力作用下做匀速直线运动,为了测定桌面与木块间由于摩擦而产生的热量,应选择下列哪组实验仪器(  )

A.量筒,温度计

B.弹簧秤,刻度尺

C.天平,秒表

D.电压表,电流表

答案

通过分析可知,拉力对木块做的功,全部转化为热,把测桌面与木块间由于摩擦而产生的热量转化为测拉力对木块做的功,因为拉力对木块做的功W=FS,所以,可用弹簧秤测出拉力,用刻度尺测出距离,然后求出功.

故选B.

阅读理解

Each year, we celebrate many holidays here in America.

On January 1, we welcome the coming of a new year like many people in other countries. And we have another four holidays on the first day of a month: April Fool’s Day, May Day, Friendship Day (Aug.1) and Grandparents Day (Sep. 1).

The most important holiday for the young people comes in February. It is Valentine’s Day. Lots of boys give red roses to girls as a present.

People celebrate some holidays for their family members. We say thanks to our mother in May and celebrate Father’s Day in the following month. In November many people return home for Thanksgiving Day, so the whole family can stay together.

There are also some interesting holidays for children. For example, Halloween comes at the end of October. Children often play with pumpkin lanterns and put on all kinds of masks.

Of course, the most important festival is Christmas. After a year of work and study, people can enjoy a long holiday, eat big meals, and visit family and friends.

小题1:How many holidays do you know on the first day of a month in America?

A.Four.

B.Five.

C.Seven.

D.Ten.小题2:What is the most important holiday for the young people?

A.Thanksgiving Day.

B.Christmas Day.

C.Valentine’s Day.

D.New Year’s Day.小题3:From the reading we know that Father’s Day comes     .

A.in May

B.in April.

C.in June

D.in July小题4: Halloween is one of the interesting holidays for.

A.children

B.mothers

C.girls

D.students小题5: Many people return home in November because they want to ___________.

A.enjoy a long holiday

B.stay with their family members

C.eat big meals with friends

D.spend Thanksgiving Day

判断题