Uses of Magnets

Q.

Why does a magnet always attract iron, not wood?

Q.

In olden days, sailors used to find direction by suspending a piece of a/an___ .

1. anchor

2. copper bar

3. sundial

4. bar magnet

Q.

In the olden days, sailors used to find direction by suspending a piece of ______ .

Q. How is an artificial magnet prepared from a natural magnet ?

Q.

Define the term.

The south pole of the magnet

Q. Magnetic compass on the earth surface always aligns itself in _____________ direction in absence of any other strong magnet beside it.

1. east-west
2. north-south
3. upward-downward
4. east-south

Q.

Which of the following is a natural magnet?

1. Bar Magnet

2. Magnetite

3. Horseshoe magnet

Q. The shapes of natural magnets are:

1. Horse-shoe
2. Cylindrical
3. Regular
4. Irregular

Q.

State one advantage of the shape of a horseshoe magnet.

Q. were the first ones who invented compass.

1. Chinese
2. Europeans
3. Indians
4. Aryans

Q.

In olden days, sailors used ___________ to find direction.

1. bar magnet

2. ring magnet

3. horse-shoe magnet

4. electromagnet

Q.

Can you get electrocuted using a multimeter$?$

Q. Greeks used to call the magical stones, which had the power of attracting iron objects, by the name ______.

1. Magnetite
2. Magnet
3. Lodestone
4. Iron bar

Q.

Magnets are used in the closing mechanism of refrigerator doors.

1. True
2. False

Q.

How can third harmonics be reduced?

Q.

Sailors can find the directions by freely suspending a piece of ______.

1. None of these

2. Bar magnet

3. Magnetic compass

4. Electromagnet

Q. Which of the following device is used by sailors to find direction?

1. Spoon
2. Compass
3. Iron
4. Plastic

Q.

Using a compass needle how would you distinguish between three bars similar in shape and appearance if one is brass, the second is an unmagnetized iron and the third is a permanent magnet?

Q. How much iron content present in the blood of female?

1. $3.5g$
2. $4g$
3. $4.5g$
4. $5g$

Q.

How can you convert iron strip into magnet?

Q. If we bring the south pole of a bar magnet close to a compass, the needle of the compass starts to point .

1. towards the magnet
2. in geographic north
3. in random direction

Q.

________ is a device used by pilots and navigators to find the direction.

1. Barometer

2. Thermometer

3. Magnetic compass

4. None of these

Q. What is an artificial magnet? State two reasons why do we need artificial magnets.

Q.

How are the artificial magnets are classified?

Q.

The neutral point of a bar magnet kept with its north pole pointing towards the north is located

Q. State whether True or False :

1. True
2. False

Q. Statement 1: A bar magnet can be used for navigation.

Statement 2: Magnets align themselves according to the magnetic field around them.

1. Only statement 1 is correct
2. Only statement 2 is correct
3. Both statements are correct
4. Both statements are incorrect

Q. If we bring the south pole of a bar magnet close to a compass, the needle of the compass starts to point .

1. towards the magnet
2. in geographic north
3. in random direction

Q. Observe the pictures A and B. The cars are initially at rest with magnets fitted on top of it as shown. Which of the following statement(s) is/are correct for the given pictures?

1. Cars 3 and 4 will come closer to each other.
2. Cars 1 and 2 will come closer to each other.
3. Cars 1 and 2 will move away from each other.
4. Cars 3 and 4 will move away from each other.

Q. Which of the following usually contains a magnet?

1. Cricket bat
2. Lemon squeezer
3. Notebook
4. Pin-holder