Primary 3 · Science · Interactions: Magnets
Interactions: Magnets questions for Primary 3 Science
10 questions to work through online, 2 of them written out the way the paper asks. Answer and you get the working straight away, then a score at the end. No sign-up, and you can retake it as often as you like.
- Magnetic materials
- Correcting a wrong rule
- Poles
- Testing whether something is a magnet
- Reading a results table
- Making and keeping a magnet
- Strength of a magnet
- Naming the poles
- Naming what happens
- Using magnets
| Object | Attracted by the magnet? |
|---|---|
| P | ✓ |
| Q | ✗ |
| R | ✓ |
| S | ✗ |
| Magnet | Paper clips picked up |
|---|---|
| J | 6 |
| K | 14 |
| L | 9 |
Answers and explanations for all 10 questions
Every answer with the reasoning behind it. Worth reading after you have tried the set — or on its own, if you are a parent marking it.
Which one of these objects would a magnet attract?
Answer: a steel paper clip
Only some metals are magnetic. Steel contains iron, so a steel paper clip is attracted; copper and aluminium are not.
Meera said 'all metals are attracted to magnets'. Which two statements together show she is wrong?
Answer: A and B only
To show the rule is wrong you need a metal that is not attracted. Copper and aluminium are both metals and neither is attracted. Plastic is not a metal, so it proves nothing about metals.
In the arrangement described above, what will happen when the two magnets are brought together?
Answer: They will attract each other.
The S pole of one is facing the N pole of the other. Unlike poles attract, so they will attract each other.
Ravi has two identical steel bars. One is a magnet and one is not. How can he tell which is which without any other equipment?
Answer: He can see whether one end of a bar repels an end of the other bar.
Attraction happens either way round, so it proves nothing. Only two magnets can repel, so repulsion is the test — and with one magnet and one plain bar, nothing will ever repel.
Based on the table, which pair of objects could P and Q be?
Answer: P: an iron nail, Q: a wooden peg
P was attracted so it must be magnetic, and Q was not so it must not be. An iron nail and a wooden peg is the only pair that fits that way round.
Which of these would make a steel nail lose its magnetism?
Answer: A and B only
Hammering and heating both knock a magnet's magnetism out of it. Stroking with a magnet does the opposite — it is one of the ways a magnet is made.
Based on the table above, what can be concluded?
Answer: Magnet K is the strongest of the three.
The magnet that holds the most clips is the strongest, and K held 14 — more than J's 6 or L's 9.
A bar magnet is hung on a thread and left to swing freely. It comes to rest pointing along the same line every time. Which pole of the magnet points towards the north? The ______ pole.
Answer: north
A freely hanging magnet settles with its north pole pointing towards the north — which is what a compass uses.
The N pole of one magnet is brought near the N pole of another. They push each other apart. What is this pushing apart called?
Answer: repulsion
Two like poles pushing apart is repulsion.
A recycling plant uses a large magnet to sort rubbish. Which rubbish will the magnet pull out?
Answer: steel food tins
Only magnetic materials are pulled out, and of these only steel food tins contain iron. Aluminium cans have to be sorted another way.