Exploring Magnets

 D. Tick (√ ) the odd-one out giving reason.

1. Allpins, others are non-magnetic.

2. Sawdust, others are used to show magnetic effect.

3. Ironsmith, others are related to discovery of magnet.

4. Silver, others are magnetic substances.

II.LOGIC BASED QUESTIONS

Short and Long Answer

1. To identify the two magnets out of the three metal bars without using any other material, you can perform the following steps:

•Take two bars and bring them close to each other at their ends.

•If the bars attract each other at both ends, at least one of them is a magnet and the other could be either a magnet or the iron bar.

•If they repel at one end and attract at the other, both are magnets because only magnets can show repulsion. Perform a similar test with the third bar and one of the two bars from the first test. If there is only attraction and no repulsion, the third bar is the iron piece.

2. (c), because there are maximum number of pins at the ends or poles.

3. When a magnet is broken into two pieces, each piece becomes a smaller magnet with its own north and south poles. However, the strength of each new magnet will be weaker than the original magnet.

4. No, it is not possible to separate the north and south poles in a magnet. Magnetic poles always occur in pairs, no isolated north pole or south pole exists.

III.HIGHER ORDER THINKING SKILLS

1. Magnets should be kept away from electronic devices because many electronic devices, such as televisions, mobiles, CDs and computers, have magnetic storage devices inside them. When an external magnet is brought near these devices, it can interfere with the magnetic components and damage them.

2. A compass needle is kept in a closed glass vessel to protect it from external influences like air currents and magnetic interference, ensuring its accuracy in pointing towards the Earth’s magnetic north.