Bar Magnets

Q. Force between two identical short bar magnets whose centre are r metre apart is 4.8N when their axes are in the same line .If the separation is increased to 2r metre the force between them is reduced to

Q. When a horse-shoe magnet is dipped in iron fillings, the attraction of the magnetic material by the poles of the magnet is:

1. can’t say
2. maximum
3. zero
4. minimum

Q.

Explain about repulsion between similar poles of 2 magnets. Is it a pull or a push?

Q. The given diagram shows two bar magnets suspended with the help of silk thread. What will be the patterns of magnetic lines of force in this situation?​

1. 
2. 
3. 
4. 

Q.

A north pole ___________ another north pole and a south pole __________ a north pole.

Q.

In ancient times, sailors found direction by suspending a ______.

1. magnetic compass

2. bar magnet

3. fish

4. electromagnet

Q. When a bar magnet is placed on a plastic plate with pins spread on it, for a given magnet:​

1. Pins stick more to the north pole of the magnet.
2. Pins stick more to the south pole of the magnet.
3. Pins stick at both the ends of the magnet of equal strength.
4. Pins stick at the center of the magnet.

Q.

Where are the poles of a bar magnet located?

1. At the middle

2. At two extreme ends

3. At one of the end together

4. Not located anywhere

Q. The following diagram shows 3 bar magnets marked as A, B and C respectively. These magnets were dipped in iron filings. By observing the figure, determine the order of magnetic strengths of the magnets A, B and C.

1. A>B>C
2. A<B<C
3. B>C>A
4. A=B=C

Q.

A magnet's power to attract metallic objects is equally distributed in its body.

1. False
2. True

Q. If a bar magnet is cut lengthwise into two parts, the total number of poles formed are:

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

Q. The strength of magnetic force of a bar magnet is maximum at both of its extreme ends.

1. True
2. False

Q. A bar magnet is immersed in a heap of iron filings and is pulled out. The amount of iron filings stuck to the_______.

1. North pole is almost equal to the South pole
2. magnet will be same all along its length
3. North pole is much less than the South pole.
4. North pole is much more than the South pole.

Q. Where are the poles of a disc magnet located?

Q.

When the South pole of a bar magnet is brought near the North pole of a ring magnet, they will _____ each other.

1. attract

2. repel

3. refract

4. reflect

Q.

Like poles of magnets ___ each other.

1. repel

2. attract

3. find

4. stick to

Q.

Where are poles of a bar magnet located?

1. in the middle

2. Bar magnet does not have poles

3. At one of the end, together

4. At two extreme ends

Q.

Which was the natural magnet found in magnesia?

1. Gemstone

2. Lodestone

3. Limestone

4. Sandstone

Q.

Which of the following magnetic ore, was once used as a primitive compass?

1. Lodestone

2. Hematite

3. magnetite

4. None of these

Q.

If a bar magnet is cut lengthwise into two parts, how many poles will be formed?

1. 6

2. 5

3. 2

4. 4

Q.

We can separate North and South pole from the same magnet.

1. None of these

2. Both A and B