Poles of a Magnet

Q.

What are the two basic laws of magnets?

Q. Two small bar magnets are placed in a line at certain distance d apart. If length of each magnet is negligible compared to d, the force between them will be inversely proportinal to

Q.

Differentiate between temporary and permanent magnets.

Q. When a bar magnet is freely suspended, it points in the north-south direction. The tip which points to the geographic north is called the _______ and the tip which points to the geographic south is called the _______ of the magnet.

1. North Pole, South Pole
2. South Pole, North Pole
3. South Pole, South Pole
4. North Pole, North Pole

Q.

What does repulsion mean?

Q. A bar magnet is immersed in a heap of iron filings and pulled out. The amount of iron filings clinging to the:

1. North pole is much more than the south pole.

2. North pole is almost equal to the south pole.

3. North pole is much less than the south pole.

4. Entire length of the bar magnet will be same.

Q.

The two ends of a magnets are called_____.

Q. The strength of a magnet is highest at the ____.

1. poles of the magnet
2. mid point of the magnet
3. North pole of the magnet
4. South pole of the magnet

Q.

Question 12

Match Column I with Column II (One option of A can match with more than one option of B)
$\begin{array}{cc}\text{COLUMN~I}& \text{COLUMN II}\\ \text{(a)Magnet attracts}& \text{(i)rests particular direction}\\ \text{(b)Magnet can be repelled}& \text{(ii)iron}\\ \text{(c)Magnet if suspended freely}& \text{(iii) by another magnet}\\ \text{(d) Poles of the magnet can be identified by}& \text{(iv)iron filings}\end{array}$

Q.

A cylindrical magnet has only one pole.

1. True
2. False

Q.

A magnetic field cannot exert any force on a

1. moving magnet

2. stationary magnet

3. moving charge

4. stationary charge

Q. The force of attraction in a magnet is maximum at :

1. Center of the magnet
2. Poles of the magnet
3. Along the breadth of the magnet
4. Along the length of the magnet

Q.

Question 10

Four identical iron bars were dipped in a heap of iron filings one by one. Fig. shows the amount of iron filings sticking to each of them.

(a) Which of the iron bar is likely to be the strongest magnet?
(b) Which of the iron bars is not a magnet? Justify your answer.

Q. Which of the following is a non-magnetic material?

1. Steel
2. Iron
3. Nickel
4. Silver

Q.

It is impossible to obtain a magnet having only one magnetic pole.

1. True

2. False

Q. Three bar magnets A, B and C are together as shown in the diagram. The poles of the magnet B are marked. Here N represents the north pole and S represents the south pole of the magnet.


Identify the south pole of the remaining two magnets.

1. $1$ and $3$
2. $1$ and $4$
3. $2$ and $3$
4. $2$ and $4$

Q. Which part of a bar magnet will attract the maximum number of iron nails when it is brought near a heap of iron nails?

1. 
   North pole
2. 
   South pole
3. 
   Near both poles
4. 
   Middle portion

Q.

Like poles of magnets attract each other.

1. True

2. False

Q.

State true or false
Non - magnetic materials: Rubber, wood, plastic.
Magnetic materials : Steel, iron nails, cobalt.

1. True
2. False

Q.

The polarity of a …………… (permanent/temporary) magnet cannot be changed.

Q.

The strength of the south pole of a magnet is greater than the strength of its north pole.

1. less than

2. greater than

Q. If the iron filings are evenly spread around a bar magnet and then the magnet is shaken a bit, most of the filings are attracted to which portion of the magnet?

1. In the middle
2. On the ends
3. Filings are evenly attracted to the magnet
4. Unpredictable

Q. Where is the force of attraction maximum in a magnet?

1. Along its length
2. Along its breadth
3. At its poles
4. At its centre

Q. Attraction is seen between the poles of two bar magnets in the case of:

1. The north pole of one magnet with the south pole of the other
2. The south pole of one magnet with the south pole of the other
3. All of the above
4. The north pole of one magnet with the north pole of the other

Q. what happends if a freely suspended bar magnet is disturbed aligned along the east -west direction

Q.

Question 6

Fill in the blanks
(i) When a bar magnet is broken; each of the broken part will have __ pole/poles.
(ii) In a bar magnet, magnetic attraction is ____ near its ends.

Q. A bar magnet is cut into two pieces A and B, from the middle, as shown in Fig.

Will the two pieces act as individual magnets? Mark the poles of these two pieces. Suggest an activity to verify your answer. [5 MARKS]

Q.

A steel bar can be magnetised permanently by rubbing a bar magnet.

1. along its length

2. at its ends

3. at its centre

4. none of these

Q.

When a South pole a magnet in brought near the N pole of a freely suspended magnetic needle, it will ___

1. It rotates

2. None of these

3. Repels

4. Attracts

Q.

A compass can be used to find the east-west direction at any place.

1. True
2. False