题目

在“探究加速度与力、质量的关系”实验中，某同学使用了如图甲所示的装置，计时器打点频率为50Hz。(1)该同学得到一条纸带，在纸带上取连续的六个点，如图乙所示，自A点起，相邻两点间的距离分别为10.0mm、12.0mm、14.0mm、16.0mm、18.0mm，则打E点时小车的速度为_____m/s，小车的加速度为_____m/s2；（结果均保留两位有效数字）(2)该同学要探究小车的加速度a和质量M的关系，应该保持_____不变；若该同学要探究加速度a和拉力F的关系，应该保持_____不变；(3)BChemical SafetyProcedures for handling chemical spills(泄露) and leaks.Chemical spills and leaks can be broken down into two basic types: simple spills, which you can clean up yourself and complicated spills, which require outside assistance.If your spill meets ANY of the following conditions, it is a COMPLICATED SPILL.? A person is injured; or? The identity of the chemical is unknown; or? Multiple chemicals are involved; or? The chemical is highly poisonous, flammable (可燃的) or reactive ; or? The spill/leak occurs in a “public space” such as a corridor; or? The spill/leak has the potential to spread to other parts of the building such as through the ventilation (通风) system; or? The clean up procedures are not known or appropriate materials are not readily available; or? The clean up requires a respirator (呼吸器) (including cartridge respirators) to be worn and no personnel have been trained and fit-tested in accordance(一致) with the campus Respiratory Protection Program; or? The spill/leak may endanger the environment by reaching waterways or outside ground, or by going down a drainIf none of the above conditions are met, the spill is defined as a simple spill. You may clean up simple spills in accordance with Chapter 6 of the Chemical Safety Guide. For consultative assistance, call Division of Research Safety (DSR) at 333-2755.How to report a complicated spill1. Evacuate(撤退) to a safe location, and alert others to evacuate.2. Dial 9-911 from a campus phone.3. Tell the operator you are calling to report a chemical spill at the University of Illinois.4. Have the following information ready.? Name of chemical? Quantity spilled? Location of spill (Full building name and room number)? Number of people injured or slashed? If applicable, the occurrence of a fire or explosion? Your name and phone number5. Have someone knowledgeable about the chemical spilled meet the fire department at the main entrance to your building. Take a Material Safety Data Sheet (MSDS) of the chemical, if it is readily available.1.Which of the following situation can be classified as a simple spill?A. Some spilled liquid causes a fire in the building.B. Yellow and green gases are leaking from the storage room.C. An unknown red chemical is found on the corridor floor.D. A researcher spills his milk all over the lab floor.2.According to the safety instructions, upon discovering a complicated spill on campus, people should _________.A. put on a respirator as soon as possibleB. refer to Chapter 6 of the Chemical Safety GuideC. get away from the spill and report it to authoritiesD. call Division of the Research Safety at 333-27553.“MSDS” in the passage possibly refers to _____.A. a maskB. an explanation about the chemicalC. a deviceD. another kind of chemical4.Who are most possibly the targeted audiences of this article?A. Students in the Chemistry Department of a university.B. Researchers working at Chemical Institution of Illinois.C. Members of Division of Research Safety.D. Staff members at a chemical manufacturing company.5.The purpose of the material above is to ____________ .A. inform people of the dangers of various chemical spillsB. introduce complicated spills and necessary measures in response to themC. encourage students to join the campus Respiratory Protection ProgramD. compare simple spills and complicated spills