Magnetism and Electromagnetism, 1-2 · © Festo Didactic 91580–P0 21 ... Place the 2 bar magnets...
Transcript of Magnetism and Electromagnetism, 1-2 · © Festo Didactic 91580–P0 21 ... Place the 2 bar magnets...
Magnetism
© Festo Didactic 91580–P0 19
Magnetic Fields
bar magnet.
The drawing shows only a few of these lines. A practical magnet has many more.
The lines near the magnet’s poles have the highest density (are closest together), so the magnetic force
is strongest here.
Midway between the poles, the lines are farthest apart, so the magnetic force here is
a. strongest.
b. weakest.
c. independent of the distance from the poles.
The lines of force for a horseshoe magnet are strongest where the poles are closest to each other.
Magnetism
20 © Festo Didactic 91580–P0
Weaker lines of force radiate outward between the poles.
Additional weaker lines travel completely around the outside of the magnet’s shape.
Their small size and weight and their magnetic properties allow a magnet to manipulate them easily.
Magnetism
© Festo Didactic 91580–P0 21
a. are repelled by the magnet.
b. are attracted to the north pole only.
c.
board.
Use the compass to identify the poles of both magnets. Which pole of each bar magnet
attracts the north pole (colored end) of the compass needle?
a. north
b. south
Magnetism
22 © Festo Didactic 91580–P0
Hold one magnet in each hand, and slowly move the south pole of one magnet toward the
north pole of the other.
Can you feel a force acting on the magnets?
a. yes
b. no
What type of force is present?
a. attractive
b. repulsive
Move the magnets apart, and reverse one magnet so that the two north poles are facing
each other. Again move the magnets together.
What type of force do you feel now?
a. attractive
b. repulsive
c. none
What type of force would you feel if you brought the two south poles together?
a. attractive
b. repulsive
c. none
Magnetism
© Festo Didactic 91580–P0 23
the bottom.
Insert a bar magnet into the indentation on top of the container, and shake the container
again.
a. They are repelled by the magnet.
b. They are attracted to the middle of the magnet.
c. They are attracted to the magnet’s poles.
a. A
b. B
c. C
a.
b. the magnet’s north pole
c. the magnet’s south pole
d.
Magnetism
24 © Festo Didactic 91580–P0
ELECTROMAGNETISM circuit board.
Place the 2 bar magnets in the holding clips as shown, with the north pole of one magnet
facing the south pole of the other.
Magnetism
© Festo Didactic 91580–P0 25
container over the 2 bar magnets. Position the container as shown so that the indentation
a. A
b. B
The lines of force appearing along the length of each magnet represent
a. a repulsive force.
b.
c.
Magnetism
26 © Festo Didactic 91580–P0
The lines of force between the north pole of one magnet and the south pole of the other
represent a(n)
a. attractive force.
b. repulsive force.
Remove the magnets, and place them in the remaining 2 clips as shown. Make sure the 2
south poles are facing each other.
Magnetism
© Festo Didactic 91580–P0 27
a. A
b. B
What type of force is shown between the 2 south poles?
a. attractive
b. repulsive
a. The same type of force exists between similar poles and opposite poles.
b. The type of force between magnets depends on whether the adjacent poles are similar or
opposite.
c.
Magnetism
28 © Festo Didactic 91580–P0
•
• The magnetic force is strongest near the magnet's poles.
•
or opposite.
1.
a. a compass.
b. a third magnet.
c. two other magnets.
d.
2. Suppose 4 bar magnets were aligned as shown (with all 4 south poles facing the center).
a. A
b. B
c. C
d. D
Magnetism
© Festo Didactic 91580–P0 29
3.
a. north to north
b. south to south
c. north to south
d. cannot be determined
4.
a. A
b. B
c. C
d. D
5.
the highlighted area?
a. attractive
b. repulsive
c. attractive and repulsive
d. None, the attractive and repulsive forces cancel each other.