问题 问答题

小明准备用天平、量筒、小烧杯测量一瓶食用油的密度,他设计了以下步骤:

A、将烧杯中的部分食用油倒入量筒中,读出体积v

B、用天平测出小烧杯和剩余食用油的质量m1

C、用天平测出装有适量食用油的烧杯的质量m2

该实验的原理是______,为了减小误差,合理的顺序是______食用油密度的表达式是p=______.

答案

实验的原理是密度的公式,即ρ=

m
V

为了避免倾倒时的残留对测量结果的影响,可先测总质量,再将一部分倒入量筒中测体积,再测剩余部分的质量,这样剩余多少都不会影响质量和体积的测量结果了.故合理的顺序为CAB;

密度的表达式:ρ=

m
V
=
m2-m1
V

故答案为:ρ=

m
V
,CAB,
m2-m1
V

填空题
阅读理解

New York Time—A gunman killed eight people at a mall in Omaha this afternoon and then killed himself, setting off panic among holiday shoppers, the police said.

“The person who we believe to be the shooter has died from self-inflicted gunshot wounds,” Sgt. Teresa Negron of the Omaha Police Department said at televised news. “We have been able to clear the mall,” she said. “We don’t believe we have any other shooters.” The police said that at least five other people had been injured in the shootings.

She did not give the shooter’s identity. “We are still conducting the investigation,” Sergeant Negron said, adding that the city’s mayor, who was out of town, was on his way back to Omaha.

    She said the police received a 911 call from someone inside the Westroads Mall on the west side of Omaha, and shots could be heard in the background. The first police officers arrived at the mall six minutes after the first call, she said, but by then the shootings were over.

    It is reported that the gunman left a suicide note that was found at his home by relatives. A law enforcement official who spoke on condition of anonymity (匿名) said the note indicated that the gunman wanted to “go out in style

The shootings broke the usually banal routine of holiday shopping. The gunman was said by some witnesses to have fired about 20 shots into a crowd. Some customers and workers ran screaming from the mall, while others dived into dressing rooms to hide from the shooter.

Shoppers and store workers were trapped inside the mall, which has roughly 135 stores. Others streamed out of mall exits with their hands raised. President Bush was in Omaha this morning to deliver a speech, but he had left the city by the time the shootings took place.

小题1: Where did the shooting first come out?

A.In a newspaper

B.On the Internet

C.In TV news

D.In a police poster小题2: What do the underlined words “go out in style” probably mean?

A.go out of the mall in particular clothes

B.walk in the mall with everybody focused on

C.go to a socially event by fashionable means

D.stop his life in a impressive way小题3: Which of the following is true according to the passage?

A.Nobody knows why the shooter did so and nothing was found at his home.

B.The city’s mayor happened not to be in the city when the shooting took place.

C.Police arrived at the mall before the shootings were over and rescued customers.

D.The official who showed what the note mean have no request of his own identity.小题4: We can infer from the passage that ______.

A.There is only one shooter in this event.

B.The shooting created fears among the customers.

C.An important holiday is coming soon.

D.President Bush came here for the shooting.