问题 选择题

甲、乙两物体从同一点开始做直线运动,其v-t图象如图2所示,下列判断正确的是(  )

图2

A.在ta时刻两物体速度相等

B.在ta时刻两物体加速度相等

C.在ta时刻之前,乙物体速度比甲物体速度大

D.在ta时刻之后,甲物体在乙物体前,并且两物体间的距离越来越大

答案

AC

速度时间图像的交点说明速度相同,斜率表示加速度大小,斜率正负表示加速度方向,所以两物体加速度大小相等方向相反,A对;B错;图线所围成的面积表示位移大小,在ta时刻之后,甲物体在前,该时刻之后甲的速度小于乙的速度,距离逐渐减小,D错;

阅读理解

Kids at the Interlake School Division were the first Canadian students to take part in a program to send experiments to the International Space Station.(ISS).

Jordan Schott and three other sixth grade students came up with the idea to test royal jelly(蜂王浆) in space . Their experiment came very close to be tested on the space station. “We were seeing if we could send it to space, and if it would lose its nutritional value” faster and or slower, ”said Schott. Schott is one of the 18 students in the Space Knights Club at Woodlands Elementary School, part of the Interlake School Division. Over 450 students from the Division took part in the program.

“I thought we were just students and we couldn’t do much in the way of that. It’s a way to communicate with people up there ,” said Braeden Clark, a seventh grade student who is also in the club.

The astronauts shared what they learned with their school with a full day of activities all about science and space.

Teacher Maria Nickel is the organizer of the club. She said the day was great for students to learn what they could do. “Space is one of those great things that get kids excited, but it also gives them the chance to do so much. They can be an astronaut; they can be an engineer, ”She said.

The day was held in honour of Chris Hadfield, a Canadian astronaut now in the Internal Space Station. “It gives kids someone more to look up to. Here’s a real hero to look up to who’s doing it all, doing it through education,” said Nickel.

Jordan Schott thinks it’s really cool. “To me it seems so cool how people can go up to space, and science is something I’ve always liked,” She said. Schott says she wants to follow in the footsteps of Hadfield and be an astronaut when she gets older.

One of the winning experiments in the competition was produced by students from Argyle, Manitoba. It will travel to the space station in the fall of 2013.

小题1:The program at the Interlake School Division________-

A.was carried out by 18 students.

B.was to test royal jelly in space

C.was designed to send experiments to the ISS

D.allowed the first students to connect with the ISS小题2:We can infer from the text that Maria Nickel__________- 

A.thinks it’s cool to live in the ISS

B.encourages students to be astronauts

C.helps students develop their interest in space

D.thinks Chris Hadfield sets a good example to the students小题3:What do we know Jordan Schott?

A.She is seventh grader

B.She dreams of being an engineer

C.She respects Chris Hadfield very much

D.She didn’t like science when she was young小题4:What’s the main idea of the text?

A.Kids carry out experiments for the ISS.

B.Winners of competitions travel to the ISS.

C.Astronauts do activities together with students

D.Interlake School Division trains students to be astronauts.

填空题