Magnets and the magnetic field
Answers are for parents and teachers.
1
A magnet is cut into 6 pieces. Total number of poles?
12
2
If the density of field lines becomes 3 times greater, how does the field change?
It becomes 3 times stronger.
3
Why does a magnetic needle line up north–south in the Earth’s field? Write briefly.
The Earth also has a magnetic field; it turns the needle along the field line.
4
Give examples of permanent magnets.
A compass needle, a fridge magnet, a loudspeaker magnet.
5
Write two safety rules for an experiment with iron filings.
Protect the eyes; do not breathe in filings or put them in the mouth.