CBSE Class 12 Physics 2025 Sample Paper Solved

[SECTION – A] 

Q1. A uniform electric field pointing in positive X-direction exists in a region. Let A be the origin, B be the point on the X-axis at x = +1 cm and C be the point on the Y-axis at y = +1 cm. Then the potential at points A, B and C satisfy.
(A) V_A < V_B.
(B) V_A > V_B.
(C) V_A < V_C
(D) V_A > V_C

Answer : B

Q2. A conducting wire connects two charged conducting spheres of radii r₁ and r₂ such that they attain equilibrium with respect to each other. The distance of separation between the two spheres is very large as compared to either of their radii.
The ratio of the magnitudes of the electric fields at the surfaces of the spheres of radii r₁ and r₂ is
(A) 𝑟₁/𝑟₂
(B) 𝑟₂/𝑟₁
(C) 𝑟₂²/𝑟₁²
(D) 𝑟₁²/𝑟₂²

Answer : B

Q3. A long straight wire of circular cross section of radius ҅a᾿ carries a steady current I. The current is uniformly distributed across its cross section. The ratio of magnitudes of the magnetic field at a point a/2 above the surface of wire to that of a point a/2 below its surface is
(A) 4:1
(B) 1:1
(C) 4: 3
(D) 3 :4

Answer : C

Q4. The diffraction effect can be observed in
(A) sound waves only
(B) light waves only
(C) ultrasonic waves only
(D) sound waves as well as light waves

Answer : D

Q5. A capacitor consists of two parallel plates, with an area of cross-section of 0.001 m², separated by a distance of 0.0001 m. If the voltage across the plates varies at the rate of 10⁸ V/s, then the value of displacement current through the capacitor is
(A) 8.85 × 10⁻³𝐴
(B) 8.85 × 10⁻⁴𝐴
(C) 7.85 × 10⁻³𝐴
(D) 9.85 × 10⁻³𝐴

Answer : A

Q6. In a series LCR circuit, the voltage across the resistance, capacitance and inductance is 10 V each. If the capacitance is short circuited the voltage across the inductance will be
(A) 10 V
(B) 10√2 V
(C) 10/√2 V
(D) 20 V

Answer : C