Arpita suspends four bars of different materials from a pillar and bring the north pole of a bar magnet near part P and Q of each bar one by one as shown in the given figure. Then she records the observations, which are given below.
Which one of the following sets correctly represents bars I, II, III and IV?
| Bar I | Bar II | Bar III | Bar IV | |
|---|---|---|---|---|
| A | Magnet | Wooden bar | Magnet | Iron bar |
| B | Magnet | Iron bar | Magnet | Glass bar |
| C | Stainless steel bar |
Magnet | Iron bar | Magnet |
| D | Magnet | Iron bar | Glass bar | Copper bar |
It should be A
Ans 2:
Class : Class 7
The correct answer is A because Bar I repels the bar magnet and only magnets can repel each other so Bar I is a magnet for sure..In Bar II nothing happens so it is an non magnetic material (wooden bar).The Bar III is also an magnet because even Bar III is showing repulsion towards the bar magnet's north pole and as told before, only magnets can repel each other.Bar IV is attracted to the bar magnet and is not showing repulsion in any side ( P or Q ) , so it is a magnetic material (iron bar). If it was a magnet it would have shown repulsion..So, the correct answer is A
Ans 6:
Class : Class 6
The correct option should be A. This is because the Bar 2 should be a Wooden bar, as it doesn't attract nor repel while placing near the magnet! According to the option they have stated as the correct one, an Iron bar doesn't do anything when placed near a magnet, but instead it attracts in both the scenarios, which is also stated in the correct option A.
Ans 8:
Class : Class 6
The answer should be (A) because a magnet can only repel each other whereas a iron bar will get attracted by both the poles of any magnet