1
AP EAPCET 2025 - 24th May Morning Shift
MCQ (Single Correct Answer)
+1
-0

A sample of paramagnetic salt contains $2 \times 10^{24}$ atomic dipoles each of dipole moment $15 \times 10^{-23} \mathrm{JT}^{-1}$. The sample is placed under homogeneous magnetic field of 0.6 T and cooled to a temperature 4.2 K . The degree of magnetic saturation achived is $20 \%$. Then total dipole moment of the sample for a magnetic field of 0.9 T and a temperature of 2.8 K is

A

$4.5 \mathrm{JT}^{-1}$

B

$13.5 \mathrm{JT}^{-1}$

C

$0.64 \mathrm{JT}^{-1}$

D

$7 \mathrm{JT}^{-1}$

2
AP EAPCET 2025 - 24th May Morning Shift
MCQ (Single Correct Answer)
+1
-0

A coil of resistance $200 \Omega$ is placed in a magnetic field. If the magnetic flux $\phi$ (in weber) linked with the coil varies with time ' $t$ ' (in second) as per the equation $\phi=50 t^2+4$, then the current induced in the coil at a time $t=2 \mathrm{~s}$ is

A

2 A

B

1 A

C

0.5 A

D

0.1 A

3
AP EAPCET 2025 - 24th May Morning Shift
MCQ (Single Correct Answer)
+1
-0

If the voltage and current in an AC circuit are respectively $50 \sin (50 t) \mathrm{V}$ and $50 \sin \left(50 t+\frac{\pi}{4}\right) \mathrm{mA}$, then the power dissipated in the circuit is nearly

A

1.296 W

B

0.648 W

C

0.884 W

D

1.768 W

4
AP EAPCET 2025 - 24th May Morning Shift
MCQ (Single Correct Answer)
+1
-0

The oscillating electric and magnetic field vectors of an electromagnetic wave are along

A

the same direction and in same phase.

B

the same direction but have a phase difference of $90^{\circ}$.

C

mutually perpendicular directions and are in same phase.

D

mutually perpendicular directions but have a phase difference of $90^{\circ}$.