Question 1
How else can magnets be used for environmental sustainability?
Cambridge Secondary (7-9). Stage 8. MCE Science. Student Book - Unit 11: Magnetism
Question 2
Work on your own to find out what a magnetic field looks like.
1. Collect a magnet, a piece of paper, some iron filings and a transparent plastic bag.
2. Place the magnet inside the bag. Place the magnet in the bag on a flat surface.
3. Rest the piece of paper on top of the magnet.
4. Pour some iron filings on the piece of paper.
5. Gently tap the piece of paper until the iron filings are spread out in a pattern.
How far from a magnet does it reach?
1. Collect a magnet, a piece of paper, some iron filings and a transparent plastic bag.
2. Place the magnet inside the bag. Place the magnet in the bag on a flat surface.
3. Rest the piece of paper on top of the magnet.
4. Pour some iron filings on the piece of paper.
5. Gently tap the piece of paper until the iron filings are spread out in a pattern.
How far from a magnet does it reach?
Question 3
Work on your own to find out what a magnetic field looks like.
1. Collect a magnet, a piece of paper, some iron filings and a transparent plastic bag.
2. Place the magnet inside the bag. Place the magnet in the bag on a flat surface.
3. Rest the piece of paper on top of the magnet.
4. Pour some iron filings on the piece of paper.
5. Gently tap the piece of paper until the iron filings are spread out in a pattern.
6. Draw the pattern that you see on the paper and compare it to the diagram in Figure 11.6. What do you observe? How similar are they?
1. Collect a magnet, a piece of paper, some iron filings and a transparent plastic bag.
2. Place the magnet inside the bag. Place the magnet in the bag on a flat surface.
3. Rest the piece of paper on top of the magnet.
4. Pour some iron filings on the piece of paper.
5. Gently tap the piece of paper until the iron filings are spread out in a pattern.
6. Draw the pattern that you see on the paper and compare it to the diagram in Figure 11.6. What do you observe? How similar are they?
Question 4
In groups, find the magnetic field between two magnets.
1. Collect two magnets, a piece of paper, some iron filings and a transparent plastic bag.
2. Place the magnets inside the bag.
3. Place the magnets on a flat surface with like poles facing each other.
4. Rest the piece of paper on top of the magnets.
5. Pour some iron filings on the piece of paper.
6. Gently tap the piece of paper until the iron filings are spread out in a pattern.
7. Repeat the process with opposite poles facing each other.
8. Explore the magnetic field all around your two magnets. Start with the arrangements shown in Figure 11.9. Then try some more of your own.
Draw the magnetic fields on a piece of paper and compare them with your classmates’.
1. Collect two magnets, a piece of paper, some iron filings and a transparent plastic bag.
2. Place the magnets inside the bag.
3. Place the magnets on a flat surface with like poles facing each other.
4. Rest the piece of paper on top of the magnets.
5. Pour some iron filings on the piece of paper.
6. Gently tap the piece of paper until the iron filings are spread out in a pattern.
7. Repeat the process with opposite poles facing each other.
8. Explore the magnetic field all around your two magnets. Start with the arrangements shown in Figure 11.9. Then try some more of your own.
Draw the magnetic fields on a piece of paper and compare them with your classmates’.
Question 5
What is a magnetic field?
Question 6
How does it affect objects around a magnet?
Question 7
What do we call two poles that are the same?
Question 8
What are two poles called when they are different from each other?
Question 9
How does Earth’s magnetic field protect us from the Sun’s dangerous effects?
Question 10
How could you test the polarity of the magnetic field in the current carrying coil?
Question 11
What would happen if you reversed the current?
[Editorial context: For the current-carrying coil in the preceding question.]
[Editorial context: For the current-carrying coil in the preceding question.]
Question 12
You can make your own electromagnet.
1 Gather these equipment: an iron nail to act as the electromagnet’s core; insulated wire to wrap around the nail; an electrical cell; connecting leads; a switch; steel paper clips.
2 Wrap the middle section of the insulated wire around the nail.
3 Use the leads to connect the wire to the electrical cell and switch.
4 Bring the paper clips close to the nail. Are they attracted?
Caution: Do not leave the current running through the wire for too long as the wires can get very hot.
1 Gather these equipment: an iron nail to act as the electromagnet’s core; insulated wire to wrap around the nail; an electrical cell; connecting leads; a switch; steel paper clips.
2 Wrap the middle section of the insulated wire around the nail.
3 Use the leads to connect the wire to the electrical cell and switch.
4 Bring the paper clips close to the nail. Are they attracted?
Caution: Do not leave the current running through the wire for too long as the wires can get very hot.
Question 13
You can make your own electromagnet.
1 Gather these equipment: an iron nail to act as the electromagnet’s core; insulated wire to wrap around the nail; an electrical cell; connecting leads; a switch; steel paper clips.
2 Wrap the middle section of the insulated wire around the nail.
3 Use the leads to connect the wire to the electrical cell and switch.
4 Bring the paper clips close to the nail.
5 Now close the switch. Are they attracted now? Why?
Invite your classmates to open and close the switch or bring the paper clips closer to the nail.
Caution: Do not leave the current running through the wire for too long as the wires can get very hot.
1 Gather these equipment: an iron nail to act as the electromagnet’s core; insulated wire to wrap around the nail; an electrical cell; connecting leads; a switch; steel paper clips.
2 Wrap the middle section of the insulated wire around the nail.
3 Use the leads to connect the wire to the electrical cell and switch.
4 Bring the paper clips close to the nail.
5 Now close the switch. Are they attracted now? Why?
Invite your classmates to open and close the switch or bring the paper clips closer to the nail.
Caution: Do not leave the current running through the wire for too long as the wires can get very hot.
Question 14
In pairs, follow the steps on page 112 and design an experiment to investigate one of the factors that influence the strength of electromagnets.
Remember to include a hypothesis and list any equipment that you may need as well as describing a procedure for carrying out the experiment.
Take turns to demonstrate one way to each other.
Remember to include a hypothesis and list any equipment that you may need as well as describing a procedure for carrying out the experiment.
Take turns to demonstrate one way to each other.
Question 15
Record your observations in a suitable form. Note any difficulties that you had.
Context: your investigation of a factor affecting electromagnet strength.
Context: your investigation of a factor affecting electromagnet strength.
Question 16
Make conclusions based on your results.
Context: your investigation of a factor affecting electromagnet strength.
Context: your investigation of a factor affecting electromagnet strength.
Question 17
Define an ‘electromagnet’.
Question 18
What happens to a wire with an electric current flowing through it?
Question 19
What happens to an iron nail when an electric current passes through it?
Question 20
Are electromagnets permanent magnets? Explain your answer.
