如图所示,是测量小灯泡电功率的实物元件图,其中电源是由三只蓄电池组成,小灯泡额定

题型:问答题

问题:

如图所示,是测量小灯泡电功率的实物元件图,其中电源是由三只蓄电池组成,小灯泡额定电压是3.8V,其灯丝电阻约为10Ω,滑动变阻器标有“10Ω、1A”字样,电流表(0~0.6A、0~3A),电压表(0~3V、0~15V).

(1)请用笔画线代替导线,把右图中的电路元件连接成实验电路.

(要求:滑片P向左移时灯变亮,且连线不得交叉)

(2)小明合理地连接好电路,并按正确的顺序操作,闭合开关后灯不亮,小明猜想:

A.可能灯丝断了

B.可能是变阻器开路

C.可能是小灯泡短路

电流表示数/A电压表示数/V原   因
06猜想______成立
00猜想______成立
请你借助电路中的电流表和电压表验证小刚的猜想,并填入上表.

(3)排除故障后,小明继续实验,调节滑动变阻器滑片,使电压表示数为______V时,小灯泡正常发光,此时电流表示数如图所示,则小灯泡的额定功率是______W.

考点:电路的连接电流的测量,电流表的使用及读数方法测量电功率的实验电功率,额定功率
题型:问答题

The most common disease in the world is the cold. It often starts with a sore throat . You sneeze and your nose runs. You usually have a headache, too. Often you have a cough later. It's not a serious disease, but you can feel quite bad. 

There isn't a cure (良药) for a cold, but you can take some medicine to make you feel better. For example, you can take aspirin (阿司匹林) to get rid of (去除) your headache. It is good to rest. and to drink a lot of water, too. A doctor once told me."With the right medicine. a cold will last for seven days. With no medicine, it will go on for a whole week!"

A long time ago, people understood that some plants made them feel better. For example, the juice of lemons (柠檬) makes a sore throat feel better. In modern times, scientists have found out which chemicals (化学药品) are in them. Man, of our medicines today are made from those chemicals. There are some diseases that we can't cure yet. And nobody has found a cure for old age. But because of modern medicines, the average people now live longer than their grandparents.

小题1:A cold often starts with _______.

A.headache

B.a cough

C.a pain in your throat

D.feeling a little cold小题2:What should we do when we catch a cold?

A.We only take some medicine.

B.We should rest well, drink much water and have some medicine.

C.We just wait for a whole week.

D.We only need a good rest.小题3:What makes a sore throat feel better?

A.The medicine aspirin.

B.A lot of water.

C.Something inside lemons.

D.The root of a plant.小题4:What is the real meaning of the doctor's words?

A.There is almost no medicine that can cure the cold.

B.There is some medicine that can cure the cold.

C.You will feel well after a whole week when you take some medicine.

D.The cold is a serious disease.小题5:From the passage. which of the following is not TRUE?

A.You can feel quite bad though the cold is not a serious disease.

B.We can get some medicine to get rid of our headache.

C.Even if you don't take any medicine, you will feel well after seven days.

D.People have found a cure for old age.

题型:问答题

属于药品监管部门的日常监督的是()

A.抽查性检验

B.注册检验

C.指定检验

D.委托检验

E.复验

题型:问答题

(14分)某同学利用玩具电动车模拟腾跃运动.如图所示,AB是水平地面,长度为L=6m,BC是半径为R=12m的圆弧,AB、BC相切于B点,CDE是一段曲面.玩具电动车的功率始终为P=10W,从A点由静止出发,经t=3s到达B点,之后通过曲面到达离地面h=1.8m的E点水平飞出,落地点与E点的水平距离x=2.4m.玩具电动车可视为质点,总质量为m=1kg,在AB段所受的阻力恒为2N,重力加速度g取10 m/s2,不计空气阻力.求:

(1)玩具电动车过B点时对圆弧轨道的压力:

(2)玩具电动车过E点时的速度;

(3)若从B点到E点的过程中,玩具电动车克服摩擦阻力做功10J,则该过程所需要的时间是多少?

题型:问答题

在计算机的软件系统中,以下不是操作系统的是

A.SUN公司开发的JAVA开发系统
B.甲骨文公司的ORACLE数据库开发系统
C.开发区企业信息管理系统
D.美国微软公司生产开发的WIN-DOWSXP系统
E.VISUALBASIC6专业版

题型:问答题

《侵略!乌贼娘》中乌贼娘的中文外号是()

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