Basic
What is an electromagnet?
A magnet made by passing electric current through a coil of wire.
How does the number of turns affect an electromagnet?
Increasing the number of coil turns makes it stronger.
How can we measure the strength of an electromagnet in an experiment?
The number of paper clips attracted.
Which is stronger: an electromagnet with 30 turns or 10 turns?
30 turns will be stronger than 10 turns.
What is an iron core?
A soft iron nail placed inside the coil.
How does increasing the current affect an electromagnet?
Adding more batteries increases the strength.
What is a fair test?
Only one variable should change at a time.
Where are electromagnets used in real life?
Scrap yard cranes use electromagnets to lift metal.
What happens around a wire carrying electric current?
A magnetic field is produced around it when current flows through it.
What happens if the iron core is removed?
Removing the iron core makes the electromagnet weaker.
What is a hypothesis?
A prediction made before the experiment.
What happens to an electromagnet when the battery is removed?
When the current stops, the magnetic field disappear
What is one advantage of an electromagnet compared to a permanent magnet?
It can be turned on and off.
Name 3 factors that affect the strength of an electromagnet.
The three main factors affecting strength are number of turns, current, and iron core.
What is a conclusion?
The final statement based on the results.
Why are electromagnets used in scrapyard cranes instead of permanent magnets?
The crane operator can control the magnet by turning the electric current on and off.
Why does wrapping the wire into a coil make the magnetic field stronger than a single straight wire?
The magnetic field lines around each loop of wire combine to form a stronger overall magnetic field.
Why might an electromagnet with many wire turns still be weak if it does not have an iron core?
Even though the number of turns was high, the electromagnet was weak because a non-magnetic core was used.
Why is it important to change only one factor at a time when testing the strength of an electromagnet?
The results are unreliable because more than one variable was changed at the same time, so it is unclear which factor caused the change.
If you needed an electromagnet to lift 50 paper clips, what changes would you make and why?
The electromagnet can lift more paper clips if the student increases the number of turns, adds more batteries, and ensures the core is soft iron, because all three factors contribute to magnetic strength.