Online Assessment
Instructions
1) Type in your first and last name in the
“Name” box in the top-left corner.
2) Next type in your teacher’s name in
the “ID” box.
3) Then type in your school’s full name in the
“Email” box.
4) Select the best answer for each question.
5) When you
are finished click the “Grade and Submit” button.
6) The grade will be emailed
to your teacher.
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1.
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NOTE: This assessment is only for Mr.
Elliott’s students.
---If you are not one of Mr. Elliott’s students then please go
back to the website and click on the link for other teachers. Thanks!
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Magnetic Resonance Imaging
(MRI) | | |
MRI machines use magnetic fields from powerful electromagnets to create images
of the inside of a persons body (see diagram above).
How are the electromagnets in a MRI machine
similar to all other electromagnets?
a. | The consist of capacitors, electrical switches, transformers, and circuit
breakers. | b. | The include hundreds of permanent magnets that can not be turned off or
on. | c. | They rotate permanent magnets through a solenoid to generate
electricity. | d. | They have coils of wire wrapped around iron cores connected to electrical
current. |
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2.
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Diagram of a Simple
Electromagnet | | |
The diagram above shows a simple
electromagnet that can lift seven paper clips
How could you modify this electromagnet so
that it would only be able to pick up two paper clips?a. | Increase the number of wire wraps in the solenoid around the iron
core. | b. | Move the iron core (the nail) back and forth through the solenoid | c. | Use a thicker wire
with the same number of wraps around the nail. | d. | Reduce the number of wire wraps in the solenoid
around the iron core. |
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3.
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Simple
Electromagnet | t
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A student makes an electromagnet and
finds that it is only strong enough to pick up one paper clip.
What modification will she need to do in order to make it pick up three paper
clips?a. | replace the battery with a bar
magnet | c. | wrap more coils around the
nail | b. | use staples instead of paper
clips | d. | use paper clips made of aluminum |
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4.
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Permanent
Magnet | Electromagnet |
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Which statement best compares a permanent magnet and an
electromagnet?a. | The magnetic field lines
from a permanent magnet emerge from the north pole, but they emerge from the south pole of the
electromagnet. | b. | A permanent magnet has a north pole and a south pole, but an electromagnet only
has a south pole. | c. | A permanent magnet requires an external source of energy, but an electromagnet
produces its own energy. | d. | A permanent magnet has a fixed magnetic field strength, but the magnetic field
strength of an electromagnet can be changed. |
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5.
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Diagram A | Diagram B | | | Device 01 | Device 02 | | |
(Two-Part Question)
(1) Identify each device shown in the two
diagrams above.
(2) What is wrong with the device in diagram A? a. | (1) Diagram B is an electromagnet, and Diagram A
is an electric motor.
(2) In Diagram B the handle is not being turned fast enough to power the
light bulb.. | b. | (1) Diagram A is a
permanent magnet, and Diagram B is an electromagnet.
(2) There is nothing wrong with device
01. | c. | (1) Diagram A is an incomplete electromagnet, and
Diagram B is a rotational generator.
(2) The wires are not connected to the battery with device
01, so there is no magnetic field. | d. | (1) The two
diagrams are both showing electromagnets being used to make electricity
(2) Device 01 will
not function properly because the wires are not connected to the
battery |
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6.
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Figure A
This figure displays an electromagnet that you could build at home from
items from a hardware store.
What are the three key components of an
electromagnet?a. | bar magnet, galvanometer, iron
core | c. | coil of wire, solenoid, source of
electricity | b. | solenoid, iron
core, source of electricity | d. | battery, paper clips, iron
nail |
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7.
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A student made an
electromagnet by wrapping copper wire around an iron nail (see diagram above). The student then
connected each end of the electromagnet to the opposite terminals of a battery.
The electromagnet will
best function as a magnet as long as...? a. | electric current flows
through the wire. | b. | electrical energy is transformed into potential
energy. | c. | the nail is made of plastic, glass, or rubber | d. | electrical energy is transformed into mechanical
energy. |
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8.
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Diagram 01 | Diagram 02 | Electromagnet | Electromagnetic Induction (Generator) | | | | |
Diagram 01:
Key components of an electromagnet: a
source of electricity, a coil of wire, and an iron core Diagram 02:
Key
components of a generator: a coil of wire, a permanent magnet, an electrical load
Contrast the two devices displayed above in diagrams 01 and 02.a. | A generator contains a battery, a coil of wire, and an iron nail.
An electromagnet
contains only a bar magnet and a coil of wire. | b. | With a battery, an iron core, and a coil of
wire, you create an electromagnet.
Generators induce electrical current via movement between a
magnet and a solenoid. | c. | An electromagnet can not be turned off and
on.
A generator can be turned off and on. | d. | An electromagnet’s magnetic field will
not move the needle on a compass
A generator’s magnetic field will move the needle on a
compass |
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9.
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A
portion of an electromagnet is shown in the diagram below.
The electromagnet will be completed by
adding...? a. | a
battery. | c. | a
switch. | b. | metal clips. | d. | insulated wires. |
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10.
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Many scrap yards use electromagnet cranes to sort and move ferrous metal
items.
How are the
electromagnets in cranes such as this similar to all other
electromagnets? a. | These electromagnets can not be turned on and off. They
are permanent magnets | b. | They have
electricity flowing through coiled wires wrapped around iron cores. | c. | The strength of the magnetic field cannot be adjusted by the crane
operator. | d. | They have aluminum cores surrounded by titanium wires
connected to electrical current |
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