Magnetic and Non Magnetic Materials

Q.

Why do magnets not stick to stainless steel?

Q. Which of the following is/are non-magnetic material(s)?

1. Iron
2. Copper
3. Cobalt
4. Wood

Q. Magnetic property of a magnet can be destroyed, if it is__________________.

1. hammered
2. heated
3. thrown from a height
4. kept under water

Q.

A perfectly diamagnetic sphere has a small spherical cavity at its centre, which is filled with a paramagnetic substance. The whole system is placed in a uniform magnetic field $B$. Then the field inside the paramagnetic substance is:

1. Much large than $\begin{array}{l}\left|\overrightarrow{B}\right|\end{array}$and parallel to $\begin{array}{l}\overrightarrow{B}\end{array}$

2. ZERO

3. $\overrightarrow{B}$

4. Much large than $\begin{array}{l}\left|\overrightarrow{B}\right|\end{array}$and opposite to $\begin{array}{l}\overrightarrow{B}\end{array}$

Q.

Question 1 (v)

Fill in the blank in the following.
A magnet always has ___ poles.

Q.

Artificial magnets were discovered in Greece.

1. True
2. False

Q. The strength of the bar magnet is _______.

1. maximum at the ends of the magnet
2. maximum at one end of the magnet
3. maximum at the middle of the magnet
4. uniform throughout the magnet

Q. Rubber is a magnetic material.

1. True
2. False

Q.

Paper is not a ______ material

Q. How many neutral point will be obtained when a bar magnet is kept with magnetic moment parallel to earth magnetic field?

Q.

If a magnet is placed on a plastic plate with pins spread on it, then________.

1. Pins stick all around the magnet

2. None of these

3. Pins stick at the middle of the magnet

4. Pins stick at the ends of the magnet

Q.

The intensity of the magnetic field due to earth at a point inside a hollow steel box is

Q.

Non - magnetic materials: Rubber, wood, plastic
Magnetic materials: Steel, iron nails, cobalt.

1. True
2. False

Q.

Which of the following gets demagnetised when a powerful magnet is kept near it?

1. Plastic ruler

2. Glass tumbler

3. Compact disc

4. Wood

Q. Which part of the magnet will most of the paper clips stick on to?

1. Only A
2. Only E
3. A and B
4. A and E

Q.

What are artificial magnets? How are these classified?

Q. Which of the following objects can be converted into magnet?

1. Iron
2. Silver
3. Gold
4. Copper

Q. If an object is attracted by both the poles of a bar magnet and not repelled by any pole, then the object can be _________.

1. a magnet
2. a magnetic material
3. a non-magnetic material
4. either a magnetic or a non-magnetic material

Q.

What is a cow magnet?

Q.

Question 7

Paheli and her friends were decorating the class bulletin board. She dropped the box of stainless steel pins by mistake. She tried to collect the pins using a magnet. She could not succeed. What could be the reason for this?

Q. Which of these would attract to a magnet if kept near it?

1. Alpins
2. Steel paper clips
3. Eraser
4. Plastic scale

Q.

Encircle the odd one out. Give reasons for your choices.

Brass, rubber, iron, paper, plastic

Q.

Why do magnetic materials have domains but non-magnetic materials don't?

Q. Steel pins sprinkled on a bar magnet concentrate at ________ of the magnet.

1. all locations
2. the middle
3. the two extremes
4. the right end

Q.

Question 2 (iv)

State whether the following statement is true or false.

Maximum iron filings stick in the middle of a bar magnet when it is brought near them.

Q.

When a piece of soft iron is rubbed with a permanent steel magnet, it also changes into a permanent magnet.

1. True
2. False

Q.

Question 8

How will you test that ‘tea dust’ is not adulterated with iron powder?

Q. Jeetu wants to make a magnet. Which of the following materials is not useful for the purpose?

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

Q. Which of the following does NOT contain a magnet in it?

1. Torch
2. Radio
3. Computer
4. Television

Q.

When a bar magnet is brought near an iron rod ________ precedes ________.