Magnetism

In which of the following situations would an electromagnet be more useful than a magnet?

• A child is linking magnetic balls together to make a necklace.

• A scrapyard worker is sorting car parts.

• A teacher uses a magnet to attach their nametag to her shirt.

• A parent is hanging a good grade on the refrigerator.

Kim is using an electric current to produce a magnetic field. She claims that when she turns off the current, the magnetic field will still continue. Which argument BEST explains why the student's claim is correct or incorrect?

• The student's claim is correct; a magnetic filed cannot disappear.

• The student's claim is incorrect; a magnetic field powered through an electric current will disappear the moment the electric current turns off.

• The student's claim is correct; whenever a magnetic field is created through an electric current, the magnetic field is still powered for some time before it disappears.

• The student's claim is incorrect; a magnetic field continues but only for a few minutes.

Tags

NGSS.HS-PS2-5

A student notices that when the fire alarms at the school go off, the doors close with the alarm and when the student tries to reconnect the door to the magnet behind the door, it will not attract. Which of the following arguments BEST describes the type of magnet the student is observing.

• The magnet is a permanent magnet because the fire alarm is connected to the door. The magnet is always turned on.

• The magnet is a temporary magnet because the fire alarm is connected to the circuit of the door. The magnet is currently turned off.

• The magnet is a temporary magnet because the fire alarm is connected to the circuit of the door. The magnet is currently turned on.

• The magnet is a permanent magnet because the fire alarm is connected to the circuit of the door. The magnet is always turned off.

A fifth grade student put a strong magnet in a plastic cup. He then put the cup with the magnet into a wood box on his desk. To his surprise, stray staples and paper clips were attracted to the magnet in the box. What statement BEST describes what the student observed?

• Magnetism can be strengthened by conductors.

• Magnetic fields pass through many materials. There is no material that will block magnetism.

• Magnetic forces only attract iron.

• Magnetism does not go through other non-metals.

Students place paper clips on a desk, and then hold a magnet under the desk. What evidence would best show that the magnetic field was able to pass through the desk?

• The paper clips move when the magnet is moved under the desk.

• The top of the desk is made of a kind of plastic.

• The magnet they are using is the largest one in the classroom.

• The students were able to pick up these paperclips with a magnet.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

A student is investigating whether the magnetic field of magnets is affected by different materials. The student wrapped a magnet with different materials and created a data chart to show the results of the investigation. Based upon the data of the investigation, what can the student conclude?

• Magnetism is blocked by any material.

• Magnetism is created by felt, paper, blanket, and leather.

• The materials prevent magnetism from going through it.

• The materials allowed magnetism to go through it.

Tags

NGSS.MS-PS2-3

NGSS.MS-PS2-5

An electromagnet is an example of this type of magnet?

• temporary

• attract

• repel

• permanent

Tags

NGSS.MS-PS2-5

This type of magnet cannot be turned off and on.

• positive charge

• temporary

• permanent

• attract

This temporary magnet can be created by wrapping an iron core with wire and connecting the wire to a battery.

• electromagnet

• temporary

• permanent

• repel

Tags

NGSS.MS-PS2-5

Like poles of a magnet do this.

• repel

• temporary

• attract

• permanent