Download App

MODEL PAPER 8 — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 81 Mark
Question
A paramagnetic sample shows a net magnetisation of $8\ Am ^{-1}$ when placed in an external magnetic field of $0.6 T$ at a temperature of $4 K$ . When the same sample is placed in an external magnetic field of $0.2 T$ at a temperature of $16 K ,$ the magnetisation will be
✓

Answer

$(b)\ \frac{2}{3} Am ^{-1}$
Explanation:
On increasing the temperature magnetic susceptibility of paramagnetic material decreases or vice versa .
According to Curie law, we can deduce a formula for the relation between magnetic field induction, temperature and magnetisation.
$i.e., I ($magnetization$) \propto \frac{B(\text { magnetic field induction })}{t(\text { temperature in kelvin })} $
$\Rightarrow \frac{I_2}{I_1}=\frac{B_2}{B_1} \times \frac{t_1}{t_2}$
Let us suppose, here $I _1=8 Am ^{-1}$
$ B _1=0.6 T, t _1=4 K$
$B _2=0.2 T, t _2=16 K$
$\Rightarrow \frac{0.2}{0.6} \times \frac{4}{16}=\frac{I_2}{8}$
$\Rightarrow I_2=8 \times \frac{1}{12}=\frac{2}{3} Am ^{-1}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from MODEL PAPER 8→MODEL PAPER 8 — all question types→Physics STD 12 Science question papers→Rajasthan Board STD 12 Science question papers→Rajasthan Board question paper generator→

Similar questions

Two point charges Q  and – 3Q are placed at some distance apart. If the electric field at the location of Q is E then at the locality of -3Q, it is(a) - E (b) E/3(c) -3E (d) -E/3
       
→
Suppose all the surfaces in the previous problem are rough. The direction of friction on $B$ due to $A:$
→
A photon of energy $8\ eV$ is incident on a metal surface of threshold frequency $1.6 \times 10^{15} \mathrm{~Hz}$, then the maximum kinetic energy of photoelectrons emitted is $\left(\mathrm{h}=6.6^{\times 10^{-34} \mathrm{Js}}\right)$
→
Two different loops are concentric and lie in the same plane. The current in the outer loop is clockwise and increasing with time. The induced current in the inner loop then, is(a) Clockwise (b) Zero(c) Counter clockwise(d) In a direction that depends on the ratio of the loop radii
 
 
 
 
→
A charged particle of mass $0.003\ gm$ is held stationary in space by placing it in a downward direction of electric field of $6 \times 10^4 N / C$. Then the magnitude of the charge is
→
If a power of 100 W is being supplied across a potential difference of 200 V, current flowing is(a) 2 A(b) 0.5 A(c) 1 A(d) 20 A
       
→
If a transparent medium of refractive index $m = 1.5$ and thickness $t = 2.5 \times 10^{–5}\  m$ is inserted in front of one of the slits of Young’s Double Slit experiment, how much will be the shift in the interference pattern? The distance between the slits is $0.5\ mm$ and that between slits and screen is $100 \ cm$
→
A metal rod of length 2 m is rotating with an angular velocity of 100 rad/sec in a plane perpendicular to a uniform magnetic field of 0.3 T. The potential difference between the ends of the rod is (a) 30 V(b) 40 V(c) 60 V(d) 600 V
       
→
A monochromatic beam of light falls on $\text{YDSE}$ apparatus at some angle $($say $q)$ as shown in figure. A thin sheet of glass is inserted in front of the lower slit $S_2$. The central bright fringe $($path difference $= 0)$ will be obtained
→
A situation may be described by using different sets of coordinate axes having different orientations. Which of the following do not depend on the orientation of the axes?
  1. The value of a scalar.
  2. Component of a vector.
  3. A vector.
  4. The magnitude of a vector.
→