What is NOT TRUE about Henry's electromagnet?A. His magnet could. hold 2,300 pounds.B. His magnet was more dangerous.C. There were more turns of wire around the iron rod in his magnet.D. His magnet was an improved model.
What is NOT TRUE about Henry's electromagnet?
A. His magnet could. hold 2,300 pounds.
B. His magnet was more dangerous.
C. There were more turns of wire around the iron rod in his magnet.
D. His magnet was an improved model.
相关考题:
One often finds a writer’s books more ________ if one knows about his life and the time when he was alive. A.comprehensibleB.comprehensiveC.comprehendedD.comprehension
He had more dictionaries than_________ for his work.() A.they are neededB.were necessaryC.it was neededD.necessary were they to him
What made the author laugh?A. His own behaviorB. His wife’s suggestionC. His changeable feelings.D. His wife’s sweet kiss.
What do we learn about Thomas Jefferson?[A] His political view changed his attitude towards slavery.[B] His status as a father made him free the child slaves.[C] His attitude towards slavery was complex.[D] His affair with a slave stained his prestige.
49) But his primary task is not to think about the moral code, which governs his activity, any more than a businessman is expected to dedicate his energies to an exploration of rules of conduct in business.
What do we learn about Thomas Jefferson?A.His political view changed his attitude towards slavery.B.His status as a father made him free the child slaves.C.His attitude towards slavery was complex.D.His affair with a slave stained his prestige.
Passage TwoQuestions 26 to 30 are based on the following passage.The electromagnet was invented in England by William Sturgeon,who took an iron rod and bent it into the shape of a horseshoe. This “horseshoe” was coated with varnish and a layer of copper wire was wrapped around it. An electric current was passed through the wire,thus making the rod magnetic. The rod was now,because of magnetic attraction,able to support nine pounds of iron. In the US,a scientist named Joseph Henry improved on Sturgeon's electromagnet by insulating the copper wine with silk. He was able to wrap many turns of wire around an iron core without danger of short circuits between the turns. His magnet could hold 2,300 pounds. This experiment prompted Henry to try his hand at converting magnetism into electricity. First he coiled some insulated wire around an iron bar. connecting both ends of the wire to a galvanometer(电流表). The iron bar was placed across the poles of the electromagnet. Then the coil of the electromagnet was connected to a battery. The galvanometer indicated a voltage,then dropped to zero. Henry signaled his assistant to disconnect the coil. The galvanometer showed that once again a voltage had been produced,although this time in the opposite direction. The principle of electromagnetic induction had thus been discovered. Unfortunately for Joseph Henry he did not publish his findings and someone else(Faraday)got the credit for the discovery.The principle of electromagnetic was discovered by______.A. William SturgeonB. Joseph HenryC. FaradayD. someone else
Why did Sturgeon's electromagnet could support nine pounds of iron?A. Because the iron rod was bent into the shape of a “horseshoe”.B. Because the rod was coated with varnish.C. Because a layer of copper wire was wrapped around the rod.D. Because the rod was made magnetic by the passing current.
In Henry's experiment,he connected the wire to______.A. a galvanometerB. an iron barC. a batteryD. an electromagnet
To be a good teacher, you need some of the gifts of a good actor; you must be able to hold the attention and interest of your students; you must be a clear speaker, with a good, strong, pleasing voice which is fully under you control; and you must be able to act what you are teaching, in order to make its meaning clear. Watch a good teacher, and you will see that he does not move motionless before his class; he stands the whole time he is teaching; he walks about, using his arms, hands and fingers to help him in his explanation, and his face to express his feeling. Listen to him, and you will hear the loudness, the quality and musical note of his voice always changing according to what he is talking about. The fact that a good teacher has some of the gifts of a good actor doesn't mean he will indeed be able to act well on the stage, for there are very important differences between the teacher's word and the actor's. The actor has to speak words which has been learnt by heart, he has1、A good teacher ______.A、knows how to hold the interest of his studentsB、must have a good voiceC、knows how to act on the stageD、stands or sits motionless while teaching2、In what way is a teacher''s work different from an actor''s? ( )A、The teacher must learn everything by heart.B、He knows how to control his voice better than an actor.C、he has to deal with unexpected situations.D、 He has to use more facial expressions.3、The main difference between students in class and theatre audience is that ( ).A、students can move around in the classroomB、students must keep silent while theatre audienceC、no memory work is needed for the studentsD、the students must take part in their teachers' plays
It was true that Freddy seemed more smarter than most of his colleagues, had read more, was altogether more _______. A.thoughtB.thoughtfulC.thinkD. thinkful
What made the author laugh?A. His own behaviorB. His wife’s suggestionC. His changeable feelingsD. His wife’s sweet kiss
A dramatist usually_______ .[A] clarifies the complicated relationship in his drama[B] makes the relationship in his drama more complicated[C] hopes to see his protagonist win an easy victory[D] likes to present his protagonist as threatening fellows
What made Professor Broad continue his search for more information on McKay?A. A uniform. of McKay.B. A footnote about McKay.C. A book on McKay.D. A picture of McKay.
You are about to go to sea and adjust the magnetic compass.To expedite the adjustment at sea,in what order should the following dockside adjustments be made ________.A.Flinders bar first,then the heeling magnet and spheresB.Heeling magnet first,then the Flinders bar and spheresC.Flinders bar first,then the spheres and heeling magnetD.Spheres first,then the Flinders bar and heeling magnet
If it __________ for his bad cold, Rick would have enjoyed more on his birthday party.A.is notB.were notC.has not beenD.had not been
Which of the following is TRUE?A.The more Jack explained, the angrier the couple gotB.Jack wanted to show his feelings through words after his experienceC.The manager went back to the table and apologized to the coupleD.From this experience, Jack learned more about American culture
Swift is a master satirist. His satire is usually masked by an outward gravity and an apparent earnestness which renders his satire all the more powerful. His "A Modest Proposal" is generally taken as a perfect model.
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单选题What is mentioned as a reason for visiting Mr. Fraser's blog?ATo give him feedback on his ideasBTo contribute to his political campaignCTo find out about his policiesDTo learn more about his political party
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单选题You are about to go to sea and adjust the magnetic compass.To expedite the adjustment at sea,in what order should the following dockside adjustments be made().AFlinders bar first,then the heeling magnet and spheresBHeeling magnet first,then the Flinders bar and spheresCFlinders bar first,then the spheres and heeling magnetDSpheres first,then the Flinders bar and heeling magnet
单选题Everyone has a right to enjoy his liberty, and _____ his life.AindeedBsoCmuch lessDmuch more
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