Understanding Electromagnets and Magnetic Fields

What direction do magnetic field lines travel around a magnet?

• North to South

• South to North

• East to West

• Randomly

What generates a magnetic field around a wire?

• Electric current

• Heat

• Sound

• Light

What shape does the magnetic field take around a straight wire?

• Ellipses

• Spirals

• Straight lines

• Circles

What does the magnetic field of a coiled wire resemble?

• A horseshoe magnet

• A spherical magnet

• A bar magnet

• A disc magnet

What is the primary way to increase the strength of an electromagnet?

• Decrease the wire thickness

• Increase the coil turns

• Use a plastic core

• Decrease the current

What effect does increasing the current through the wire have on an electromagnet?

• Decreases its strength

• Increases its strength

• Makes it unstable

• No effect

What core material enhances an electromagnet's strength?

• Silver

• Copper

• Iron

• Aluminum

What is the purpose of increasing the number of turns in an electromagnet's coil?

• To reduce its efficiency

• To increase its strength

• To decrease its power consumption

• To make it look bigger

In an experiment, what variable would you change to test electromagnet strength?

• Color of the wire

• Number of coil turns

• Length of the wire

• Type of metal in the core

What is a dependent variable in the electromagnet strength experiment?

• Number of nails picked up

• Room temperature

• Wire material

• Type of power supply