1
AP EAPCET 2025 - 21st May Morning Shift
MCQ (Single Correct Answer)
+1
-0

A closely wound solenoid of 1200 turns and area of cross-section $5 \mathrm{~cm}^2$ carries a current. If the magnetic moment of the solenoid is $1.2 \mathrm{JT}^{-1}$, then the current through the solenoid is

A

2.5 A

B

2 A

C

3 A

D

1.5 A

2
AP EAPCET 2025 - 21st May Morning Shift
MCQ (Single Correct Answer)
+1
-0

If the magnetic field inside a solenoid is $B$, then the magnetic energy stored in it per unit volume is ( $c=$ speed of light in vacuum and $\varepsilon_0$ is permittivity of free space)

A

$\varepsilon_0 c^2 B^2$

B

$\frac{\varepsilon_0 c^2 B^2}{2}$

C

$2 \varepsilon_0 c^2 B^2$

D

$\frac{\varepsilon_0 c^2 B^2}{4}$

3
AP EAPCET 2025 - 21st May Morning Shift
MCQ (Single Correct Answer)
+1
-0

The resonant frequency of an LC circuit is $f_0$. If a dielectric slab of constant 16 is inserted completely between the plates of the capacitor, then the resonant frequency is

A

$\frac{f}{2}$

B

26

C

$\frac{6}{4}$

D

$4 f$

4
AP EAPCET 2025 - 21st May Morning Shift
MCQ (Single Correct Answer)
+1
-0

In a plane electromagnetic wave, the magnetic field is given by $\mathbf{B}=3 \times 10^{-7} \sin \left(100 \pi x+10^{12} t\right) \mathrm{T}$, then the wavelength of the wave is

(In the equation $x$ is in metre and $t$ is in second)

A

0.02 m

B

0.2 m

C

0.4 m

D

0.04 m