Name:_____
Class Period: ____
Date:______
MAGNETS & MOTORS PRE-TEST
Multiple Choice: Circle the best answer
1. An example of a magnetic material is
a)Copper
b)Rubber
c)Nickel
d)Aluminum
2. If you place the poles of two magnets next to each other and feel them push away from each other
then they must be
a)The same, so they attract each other
b)The same, so they repel each other
c)Opposites, so they attract each other
d)Opposites, so they repel each other
3. Magnetism is a
a)Type of energy
b)Type of particle
c)Type of motion
d)Type of force
4. A compass needle always lines up with the ______of the nearest magnet
a)Magnetic south pole
b)Iron filings
c)Electromagnet
d)Magnetic Field
5. Electricity is the flow of ______from one place to another
a)Neutrons
b)Protons
c)Electrons
d)Atoms
6. When a battery is hooked up to a wire, chemical energy in the battery is changed into
a)Electrical energy
b)Heat energy
c)Light energy
d)Motion energy
7. The strength of an electromagnet can be increased by
a)Increasing the number of coils
b)Wrapping the coils around an iron bolt
c)Adding more batteries to the circuit
d)All of the above
8. Electrical energy is changed into mechanical (motion) energy by a
a)Motor
b)Generator
c)Electromagnet
d)Electrical outlet
9. Mechanical (motion) energy is changed into electrical energy by a
e)Motor
f)Generator
g)Electromagnet
h)Electrical outlet
10. All electric motors have an automatic switch to
a)Keep it from overheating
b)Light a light bulb
c)Spin the electromagnet
d)To save the battery
11. Two 6th grade students were planning an investigation about magnets and motors. Their question was, “How does the number of batteries affect how fast a motor spins?” What was their manipulated variable?
a)The speed of the motor
b)The number of batteries
c)The number of coils
d)The number of electromagnets
12. What was their responding variable?
a)The speed of the motor
b)The number of batteries
c)The number of coils
d)The number of electromagnets
Short Answer Part 1: Answer in complete sentences (4 pt.)
13. Make a list of numbered steps to describe howan electric motor works. You must use the following words in your answer:
BATTERY COIL MAGNETIC FIELD MAGNET REPEL
______
True or False: Circle the best answer (1 pt. each)
14. T or F: The Earth has a giant magnetic field.
15. T or F: Magnetic poles that are the same (N and N or S and S) attract each other.
16. T or F: A coil must have an electric current flowing through it to be an electromagnet.
17. T or F: It you stroke an iron object with a magnet it will temporarily become a magnet.
18. T or F: Electromagnets are temporary magnets.
19. T or F: Electricity cannot flow through a circuit if it is closed.
20. T or F: Magnetism is a force that attracts iron objects.
21. T or F: In order to keep spinning, a motor must have an automatic switch.
22. T or F: Electric motors do NOT require a magnet to work.
23. T or F: The Earth’s north pole is in the same place as its magnetic north pole.
Fill in the Blank with the Best Answer (2 pts. each)
24. A pathway for an electrical current is called a ______.
25. When electricity moves through a wire, a ______forms around the wire.
26. To make a motor spin, one pole of the permanent magnet has to ______the pole on the electromagnet.
27. All simple motors have a ______, an ______, and a source of energy.
28. An electric motor is a device that uses magnets to change ______energy into
______energy.
GO ON TO THE NEXT PAGE!
Short Answer Part 2: Answer in complete sentences (4 pts. Each)
29. a) Look carefully at the picture of the simple motor below. Label the motor’s permanent magnet(s), electromagnet(s) and the source of energy. b) Label on the diagram the three different types of energy that occur in this motor.
30. Imagine that you and your troop did an experiment about the strength of electromagnets. The question you investigated was, “How does the number of batteries affect how many paper clips an electromagnet could pick-up?”Pretend that this data table shows your results.
# of Paper Clips Picked-Up
# of Batteries / Trial 1 / Trial 2 / Trial 3 / Average1 Battery / 3 / 2 / 2 / 2.3
2 Batteries / 4 / 4 / 6 / 4.6
3 Batteries / 8 / 7 / 9 / 8.0
4 Batteries / 12 / 13 / 12 / 12.3
a.) Look at the table above then answer the question: How does the number of batteries affecthow many paper clips an electromagnet could pick-up? ______
b.) Use two pieces of evidence from the data table to support your answer.