Temporary Magnetisation

Q. How can you convert an iron bar into a magnet?

1. By hammering it.
2. By rubbing a magnet on it for a few minutes.
3. By keeping it in a hot glass of water.
4. By freezing it.

Q. Is magnet a conductor? if it is a conductor it is good or bad conductor

Q. Why is it said that repulsion is a sure test for magnetism?

Q.

Describe an activity to show how an iron nail/ bar can be magnetized.

Q.

We can make a piece of an iron metal temporary magnet by rubbing a magnet on its surface.

1. True

2. False

Q.

True or False

1. It is a healthy practice to burn leaves to dispose them of.
2. Solid carbon dioxideis called dry ice.
3. Water table can be go down by less rainfall.
4. Copper metal is a magnetic material.
5. Fuse wire has low melting point wire.

Q.

While magnetizing an iron piece, why do we move only one pole of the magnet over the iron piece?

Q.

A metal piece cannot be magnetized using a bar magnet.

1. True

2. False

Q.

Some conductors can be made into a magnet.

1. True

2. False

Q. How will you test that ‘tea dust’ is not adulterated with iron powder?

Q. Why is it said that repulsion is a sure test for magnetism?

Q. Which of the following is used to make permanent magnets ?

1. Steel
2. Copper
3. Soft iron
4. Nichrome

Q.

Which of the following statements are correct?

1. Retentivity is the ability to retain the magnetism

2. Soft iron has a very high susceptibility

3. Wood has a very high susceptibility

4. Steel has a very low retentivity

Q. Satish magnetised a piece of iron marked W, X, Y and Z using the rubbing method as shown in the figure.

Which of these parts of the iron piece will become the north pole?

1. W
2. X
3. Y
4. Z

Q. The strength of the magnet after heating.

1. increases
2. decreases
3. remains same

Q. How will you test that ‘tea dust’ is not adulterated with iron powder?

Q. Which of the following materials is most appropriate to make a good temporary magnet?
(a) iron
(b) cotton
(c) glass
(d) wood

Q. Which of the following metal gets attracted to a magnet?

1. Iron
2. Silver
3. Aluminium
4. Gold

Q. Which of the following methods can't be used to demagnetise a magnet?

1. Dropping
2. Heating
3. Rubbing
4. Cooling
5. Breaking
6. Hitting
7. Wetting
8. Kept Unused

Q. In the process of magentising an iron piece, where will the north pole be formed?

1. 
2. 
3. 

Q.

You are given an iron strip. How will you convert it into a temporary magnet?

1. By putting it into hot water.

2. By placing a magnet near it for few hours.

3. By rubbing it with a magnet for few minutes.

4. It can't be converted.