Bihar Board (BSEB) - Class 12 (Intermediate) previous year questions (PYQ)

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Work done by an electrostatic field in moving a test charge along a closed path is zero.

Reason (R): The electrostatic Coulomb force is a conservative force whose line integral around any closed loop vanishes identically.

What happens to the total equivalent resistance ($R_{eq}$) of a domestic circuit when three 100 $\Omega$ appliances are added in parallel?

Higher Academic Core: In advanced conceptual study of 'वैद्युतरसायन (Electrochemistry)' in Physical, Inorganic & Organic Chem, which foundational mechanism is universally verified?

Refer to the Case Study 'Case Study: Optical Fibers and Total Internal Reflection in Medical Endoscopy' to answer:

What is the primary function of the outer cladding layer in the fiber structure?

गुणा, भाग एवं ऐकिक नियम: 'सदिश बीजगणित (Vector Algebra)' के आधार पर एक इकाई का मान ज्ञात करने हेतु कौन-सी संक्रिया होगी?

Directions: In the following question, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Gandhiji decided to call off the Non-Cooperation Movement in February 1922.

Reason (R): A violent confrontation occurred at Chauri Chaura in Gorakhpur district, where an agitated crowd set a police station on fire, killing 22 policemen.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Electric current in a conductor is treated as a scalar physical quantity.

Reason (R): Although electric current has both magnitude and direction, it does not obey the laws of vector addition.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): A convex mirror is commonly used as a driver's rear-view mirror in automobiles.

Reason (R): A convex mirror always forms an erect, virtual, and diminished image, providing a much wider field of view.

गणित की दुनिया (बिहार प्राथमिक): 'समाकलनों के अनुप्रयोग (AOI)' की मूल संकल्पना क्या दर्शाती है?

Directions: In the following question, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Individuals afflicted with sickle-cell trait ($Hb^A Hb^S$) exhibit high resistance to malignant falciparum malaria.

Reason (R): Sickle hemoglobin undergoes sickling upon deoxygenation, causing premature phagocytic lysis of parasitized RBCs by spleen macrophages.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Diamond sparkles brilliantly with internal radiance.

Reason (R): Total internal reflection of light occurs inside diamond because its critical angle is exceptionally small (approximately 24.4°).

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): A concave mirror can form both real inverted images and virtual erect images.

Reason (R): When an object is placed between the pole and focus of a concave mirror, it forms an erect, magnified, virtual image.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Danger signals on communication towers and traffic posts are always illuminated in red color.

Reason (R): Red light has the longest wavelength in the visible spectrum and suffers minimum Rayleigh scattering ($I \propto 1/\lambda^4$) through fog and smoke.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Energy flow through ecological food webs is strictly unidirectional.

Reason (R): Solar energy captured by autotrophic producers is dissipated as metabolic heat and cannot revert back to solar radiation, diminishing at successive trophic levels.