Chapter 21. You and your teammates will each take turns answering review questions. If correct, your team will earn a point. You also will have a.

BOZO BUCKET REVIEW

Chapter 21Chapter 21

You and your teammates will each take turns answering review questions.

If correct, your team will earn a point. You also will have a chance to shoot a paper wad into the trash bin from a designated distance.

If you make your basket, your team will earn an additional one, two, or three points!

RULES OF GAME

1 2 3 4 5 6 7 8 9 10

11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30

31 32 33 34 35

QUESTIONS

Question 1

Earth’s magnetic field and a bar magnet both attract particles to the same locations. Where are they?A) the middle of the magnetB) all around the outsideC) the North and South polesD) first to the middle, then to the ends

Question 2

What must happen for an electromagnet to have a magnetic field?A) It must be heated.B) It has to be touching another magnet.C) It must be lined up with Earth’s magnetic

field. D) It must be connected to an electrical source.

Question 3

What happens when two south poles of magnets are placed together? A) they repel each otherB) they attract each otherC) they cancel each other outD) the strength of the magnet is doubled

Question 4Ancient people discovered magnetic

rocks called lodestone. What did they use them for?A) to start firesB) compassesC) sculpturesD) telephone receivers

Question 5

If two magnets were in this order: SN SN, they would:A) repel each otherB) attract each otherC) do nothingD) none of the above

Question 6

You can tell if an object is magnetic if the grouping of atoms:A) Are scattered in all different directions.B) Are lined up in the same direction.C) Are lined up in opposite directions.D) Are half lined up and half scattered.

Question 7How can you make a magnet lose its

magnetism?A) by heating itB) by blowing on itC) by hitting it very hardD) both A and C

Question 8

A current carrying coil with many loops is called a(n) _________________.

Question 9

If you add more coils to a solenoid or increase the current, what happens to the strength of an electromagnet?

Question 10

The flow of charges through a material is called _________________.

Question 11How many days of school are left?

(Don’t count today, holidays, or Saturdays or Sundays)

Question 12A material through which charge can

flow easily is known as a(n) __________________.

Question 13A complete path through which electric

charges can flow is known as a(n) ________________.

Question 14What subatomic particle in an atom

gives it a magnetic field?

Question 15What is the name of the device that

has a magnetized needle that can spin freely?

Question 16

An electric generator converts ____________ energy into ___________ energy.

Question 17A transformer increases or decreases

A) energyB) resistanceC) voltageD) direct current

Question 18

What happens to the poles when you break a bar magnet in half?

Question 19

True or False: Moving a magnet relative to a coil of wire induces a current in the wire if the coil is part of a complete circuit.

Question 20Nickel is considered a(n)

_________________ material because it contains magnetic domains.

Question 21A solenoid with a ferromagnetic core is

called a(n) ___________________.

Question 22This is the area that is influenced by

the Earth’s magnetic field.

Question 23

This is a device with fanlike blades that converts energy from various sources to electrical energy.

Question 24

Name two types of generators.

Question 25

An electronic device contains a transformer. Its primary coil has 200 turns, and its secondary coil has 20 turns. If the device is plugged into a 120-volt line, what is the output voltage of the device?

Secondary coil turns = output voltage

Primary coil turns input voltage

Question 26This device is used by doctors to create

more detailed images of the human body than are possible with X-rays.

Question 27What day is your final exam on for your

class?

Question 28What type of magnet keeps its

magnetism for a long time?

Question 29A magnet’s field lines always start near

the magnet’s ____________ pole.

Question 30Electromagnetic devices like an electric

motor convert ___________ energy into ____________ energy.

Question 31

What causes a ferromagnetic material to become magnetic?A) unpaired electronsB) paired electronsC) unpaired protonsD) paired protons

Question 32

A galvanometer is a device used to measure ________________.

Question 33True or False: In an alternating current

produced by an AC generator, the flow of direction of charges switches back and forth.

Question 34

A charge moving in a magnetic field will be deflected in a direction that is ____________ to both the magnetic field and to the velocity of the charge.

Question 35

A ____________ transformer decreases the voltage so that it can enter homes safely.

Answer Key

1. C

2. D

3. A

4. B

5. B

6. B

7. D

8. solenoid

9. increases strength

10. current

11. 11 days

12. conductor

13. circuit

14. electron

15. compass

16. mechanical, electrical

17. C

18. each magnet has a N & S pole

19. True

20. ferromagnetic

21. electromagnet

22. magnetosphere

23. turbine

24. AC and DC generators

25. 12 volts

26. MRI

27. day varies w/ class hour

28. permanent

29. north

30. electrical, mechanical

31. A

32. current

33. True

34. perpendicular

35. step-down