Magnets

Q. A magnet is made of:

1. Copper or aluminium
2. Aluminium or iron
3. Steel or copper
4. Steel or iron

Q. Which of the following is true about magnetic poles?

1. They always exist separately.
   
2. They may exist separately.
3. They always exist in pairs.
4. Their position changes with time.
   

Q.

Three identical iron bars are kept on a table. Two out of three bars are magnets. In one of the magnets, the north-south poles are marked. How will you find out which of the other two bars is a magnet? Identify the poles of this magnet.

Q. A bar magnet is broken into three pieces. How many poles do we have now?

1. Eight
2. Six
3. Three
4. Two

Q. A magnet can be made from any metal.

1. True
2. False

Q. Which of the following ways will cause the magnet to lose its magnetic properties?

1. Touching it to an iron piece
2. Covering it with a layer of oil
3. Heating it for a long time
4. Touching it to a wood piece

Q. A bar magnet is split into five pieces. How many poles in total will exist now?

1. Two
2. Five
3. Zero
4. Ten

Q. An object is attracted by one pole of a magnet, and repelled by the other pole of the magnet. The object is a magnet itself.

1. False
2. True

Q. Magnetic compass is made of a __________.

1. bar magnet
2. ring magnet
3. horseshoe magnet
4. disc magnet

Q.

Describe the steps involved in magnetizing an iron strip with the help of a magnet.

Q. Which among the following is necessary to convert an iron bar into a magnet?

1. Another identical iron bar
2. A bar magnet
3. Any metallic bar
4. Any magnetic material

Q.

Name the ore of iron in which magnetism was first discovered. What is its chemical formula?

Q.

Repulsion is the sure test of magnetism.

1. True
2. False

Q. Permanent magnets in the ancient times may have been formed due to:
A. Lightning
B. Earth's magnetism
C. Thundering

1. Only A
2. Only B
3. A and B
4. A, B, and C

Q.

An iron bar CD is now brought first near the north pole and then near the south pole of the freely suspended magnetic compass. It is observed that it

attracts both the poles of magnetic compass. Is CD a magnet or a magnetic substance.

Q. On a table, a weak magnet Y is placed near a strong magnet X, which is firmly fixed on the table, as shown in the figure below.

1. Y will not turn at all.
2. Y will turn in the clockwise direction.
3. Y will turn in the anticlockwise direction.
4. Cannot be determined.

Q.

If a given material repels one pole of a magnet the given material is a _______.

Q. Which among the following statements is false regarding magnets?

1. They attract certain materials such as iron and nickel.
2. They produce heat when placed in sunlight.
3. When freely suspended, they align themselves in the direction of Earth's magnetic field.
4. They exert an attractive or repulsive force on other magnets.

Q. magnet attracts metal objects to prevent hardware disease in cows.

1. Bar
2. Horseshoe
3. Rumen

Q. Permanent magnets in the ancient times may have been formed due to:
A. Lightning
B. Earth's magnetism
C. Thundering

1. Only A
2. Only B
3. A and B
4. A, B, and C

Q.

What is the sure test of a magnet?

Q. Find the total number of poles if a magnet is broken into two halves.

1. 2
2. 4
3. 0
4. 6

Q.

An iron bar CD is brought first near the north pole and then near the south pole of the freely suspended magnetic compass. It is observed that it attracts both the poles of magnetic compass. Is CD a magnet or a magnetic substance.

Q. Find the total number of poles if a magnet is broken into two halves.

1. 2
2. 4
3. 0
4. 6

Q.

The materials which are attracted towards a magnet are called ______.

1. magnetic materials
2. non-magnetic materials
3. conductors
4. insulators

Q. The effective length of the magnet is

1. The complete length of the magnet
2. The distance between the two poles of the magnet
3. The half of the length of the magnet
4. The square of the length of the magnet

Q. On a table, a weak magnet Y is placed near a strong magnet X, which is firmly fixed on the table, as shown in the figure below.

1. Y will not turn at all.
2. Y will turn in the clockwise direction.
3. Y will turn in the anticlockwise direction.
4. Cannot be determined.

Q. Materials which are attracted to a magnet are known as

1. magnetic materials
2. conductors
3. non-magnetic materials
4. insulators