Tag: magnetic materials

Quizzes (0) Questions (35)

Questions Related to magnetic materials

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

Domain formation is the necessary features of

  1. Diamagnetism

  2. Paramagnetism

  3. Ferromagnetism

  4. All of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ferromagnetism materials exhibit a long range ordering phenomenon at the atomic level which causes the unpaired electron spins to line up parallel with each other in a region called domain. Within the domain, the magnetic field is intense, but in a bulk sample the material will usually be unmagnetised because the many domains will themselves be randomly oriented with respect to one another. Hence, domain formation is the necessary feature of ferromagnetic substance.

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

If a solution of ferromagnetic material is poured into a U-tube and one arm of this is placed between the poles of a strong magnet with the meniscus in line with the field, then the level of the solution will:

  1. Rise

  2. Fall

  3. Rise till the liquid comes out

  4. Remain unchanged
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ferromagnetic materials are strongly attracted to magnetic fields. When placed in a non-uniform magnetic field (like between the poles of a magnet), the liquid will be pulled toward the region of higher field strength, causing the level in that arm to rise.

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

The value of magnetic susceptibility for para-magnetic substance is  

  1. infinity

  2. low positive

  3. low negative

  4. zero
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Paramagnetic substance gets feebly magnetised in the direction of field and therefore, $I$ is very small and positive for paramagntic substances.
We know $X _m=I/H$
Therefore,$X _m$ is also very small and positive.

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

Relative permittivity and permeability of a material are $\varepsilon _{r}$ and $\mu _{r}$ respectively. The values of these quantities allowed for a diamagnetic material are

  1. $\varepsilon _{r}=0.5,\mu _{r}=1.5$

  2. $\varepsilon _{r}=1.5,\mu _{r}=0.5$

  3. $\varepsilon _{r}=0.5,\mu _{r}=0.5$

  4. $\varepsilon _{r}=1.5,\mu _{r}=1.5$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For diamagnetic material
$0\leq \mu _{r}< 1$
And for any material, $ \varepsilon _{r}> 1$

So, option B.

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

Magnetism is a property present in ___________.

  1. Only a few materials

  2. Only ferromagnetic material

  3. Only paramagnetic material

  4. All materials
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Magnetization is present in all materials. It is a class of physical phenomenon that is mediated by Magnetic fields.

The magnetic state of different materials depends on temperature and other variables such as pressure and applied magnetic field.

 

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

Relative permittivity and permeability of a material are $\epsilon _{\mathrm{r}}$ and $\mu _{\mathrm{r}}$, respectively. Which of the following values of these quantifies are allowed for a diamagnetic material? 

  1. $\epsilon _{\mathrm{r}}=0.5,\ \mu _{\mathrm{r}}=0.5$

  2. $\epsilon _{\mathrm{r}}=1.5,\ \mu _{\mathrm{r}}=1.5$

  3. $\epsilon _{\mathrm{r}}=0.5,\ \mu _{\mathrm{r}}=1.5$

  4. $\epsilon _{\mathrm{r}}=1.5,\ \mu _{\mathrm{r}}=0.5$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

For a diamagnetic material, $\mu _r$ and $\epsilon _r$ should have following bounds $0<\mu _r <1$ and for any material $\epsilon _r >1$

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

Needles $N _{1}, N _{2}$ and $N _{3}$ are made of a ferromagnetic, a paramagnetic and a diamagnetic substance respectively. A magnet when brought close to them will 

  1. attract all three of them.

  2. attract $\mathrm{N} _{1}$ and $\mathrm{N} _{2}$ strongly but repel $\mathrm{N} _{3}$.&nbsp;

  3. attract $\mathrm{N} _{1}$ strongly, $\mathrm{N} _{2}$ weakly and repel $\mathrm{N} _{3}$ weakly.

  4. attract $\mathrm{N} _{1}$ strongly, but repel $\mathrm{N} _{2}$ and $\mathrm{N} _{3}$ weakly.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Ferromagnetic substances are strongly attracted by a magnet while, paramagnetic and diamaganetic substances are weakly attracted and repelled respectively.

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

Curie temperature is the temperature above which 

  1. a ferromagnetic material becomes paramagnetic

  2. a paramagnetic material becomes diamagnetic

  3. a ferromagnetic material becomes diamagnetic

  4. a paramagnetic material becomes ferromagnetic.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Curie temperature is the temperature above which ferromagnetic materials lose their permanent magnetic field, the magnetism completely disappears. Above Curie temperature, the material behaves para-magnetically.

Multiple choice physics magnetism and matter magnetic materials behaviour of substances in magnetic field classification of magnetic materials

A ferromagnetic material is placed in an external magnetic field. The magnetic domains 

  1. Increase in size

  2. Decrease in size

  3. May increase or decrease is size

  4. Have no relation with the field
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When a ferromagnetic material is placed in an external magnetic field, the magnetic domains that are aligned with the field grow in size at the expense of those that are not, leading to magnetization.