Discovery of Magnets

Q.

Which of the following is not used for making permanent magnets?

1. Cobalt

2. Nickel

3. Silver

4. Iron

Q.

Magnetite is a/an___magnet

Q. Which metal does a magnetite rock contains?

1. Magnesium
2. Cobalt
3. Iron
4. Zinc

Q. Harish was asked to identify a soft iron placed in a basket with 9 other magnets of the same shape and size. Which is the easiest way of identifying the iron piece at the earliest?

1. By conducting repulsion test using any two magnets at a time.
2. By suspending the magnets one at a time.
3. By dropping all the magnets into the water.
4. By heating all the magnets together.

Q.

What is a lodestone?

Q.

Which was the natural magnet found in magnesia?

Q. Articles from which of the following groups can be attracted by magnets but cannot attract other objects?

P	Q	R
Magnets	Non-Magnetic substances	Magnetic substances

1. Only P
   
2. P and R
   
3. Only Q
   
4. Only R
   

Q.

Write any two uses of a magnet. [2 MARKS]

Q. Which of the following has magnetic properties?

1. Lodestone
2. Pure silver
3. Plastic
4. Wood

Q.

A compass has a small balanced pointer that always points in the North-South direction. This is because of the earth's___field.

Q.

Provided a metal piece and a thread, what else is necessarily required to find out if the metal piece is a magnet or not?

1. A piece of magnetic substance.

2. We do not require anything more.

3. A magnet or a compass.

4. A piece of non-magnetic substance.

Q. A magnetic compass needle is not aligning itself in the north-south direction. What could be the possible reason(s) behind this?

1. The magnetic compass is defective.
2. Some external magnets are present near the compass.
3. There is no magnet near the compass needle.
4. Earth’s magnetic field is not present at that place.

Q. What is the difference between a temporary and a permanent magnet?

Q. What must a bar be made of to become a permanent magnet?
(a) steel
(b) stainless steel
(c) aluminium
(d) iron

Q. Choose an incorrect statement regarding a compass.

1. The compass needle is a type of magnet.
2. Compass is a device used for finding directions.
3. Magnet of the compass needle has only one pole.
4. The needle of the compass always points in a north-south direction.

Q. Choose an incorrect statement regarding a compass.

1. The needle of the compass always points in a north-south direction.
2. Compass is a device used for finding directions.
3. The compass needle is a type of magnet.
4. Magnet of the compass needle has only one pole.

Q. Harish was asked to identify a soft iron placed in a basket with 9 other magnets of the same shape and size. Which is the easiest way of identifying the iron piece at the earliest?

1. By suspending the magnets one at a time.
2. By conducting repulsion test using any two magnets at a time.
3. By heating all the magnets together.
4. By dropping all the magnets into the water.

Q. Find the odd one out :
Magnetite, Magnes, Magnesia, Bar magnet

1. Magnetite
2. Magnes
3. Magnesia
4. Bar magnet

Q. Which metal does a magnetite rock contains?

1. Magnesium
2. Cobalt
3. Iron
4. Zinc

Q. Magnetite contains which metal ?

1. Steel
2. Copper
3. Iron
4. Aluminium

Q. An instrument which uses magnet to give direction is known as :

1. compass
2. vacuum cleaner
3. motor
4. Magna lock

Q. What is a magnet?

Q.

Question 2 (ii)

State whether the following statement is true or false.

Artificial magnets were discovered in Greece.

Q. Dev was asked to identify a soft iron placed in a basket with 9 other magnets of the same shape and size. Which is the easiest way of identifying the iron piece at the earliest?

1. By suspending the magnets one at a time.
2. By conducting repulsion test using any two magnets at a time.
3. By heating all the magnets together.
4. By dropping all the magnets into the water.

Q.

Which of the following was the first magnet discovered:

1. Magnetite

2. Steel

3. Cobalt

4. Iron

Q. Name two materials that can be used to make a permanent magnet.

Q. Magnet was found in a place called :

1. Asia
2. Europe
3. Magnesia
4. Denmark

Q. Harish was asked to identify a soft iron placed in a basket with 9 other magnets of the same shape and size. Which is the easiest way of identifying the iron piece at the earliest?

1. By suspending the magnets one at a time.
2. By conducting repulsion test using any two magnets at a time.
3. By heating all the magnets together.
4. By dropping all the magnets into the water.

Q. A magnetic compass needle is not aligning itself in the north-south direction. What could be the possible reason(s) behind this?

1. The magnetic compass is defective.
2. Some external magnets are present near the compass.
3. There is no magnet near the compass needle.
4. Earth’s magnetic field is not present at that place.

Q.

differentiate between permanent and Temporary magnet