List of top Questions asked in Bihar Board Class XII

On what two factors does the capacity of a condenser depend?
What do you understand by capacity of any conductor? Find an expression for the capacity of a cylindrical condenser.
Lenz's law follows the law of conservation of energy. Explain.
What is photo-cell? Write down its two applications.
The decay constant of a radioactive substance is 5.2 x 10\(^3\) per year. What is its half-life?
What is Curie law?
What are '\(\alpha\)' and '\(\beta\)' parameters of transistor? What is their relation?
Differentiate between primary and secondary rainbows.
Under what condition will the magnifying power of a microscope be maximum?
What is carbon dating?
A convex lens of refractive index 1.5 is kept in a liquid medium having same refractive index. What is the focal length of the lens in this medium?
Write down truth table and Boolean expression for NOR and NAND gates.
For resonance condition in any L-C-R circuit, the phase-difference between applied voltage and current is
In step-up transformer, the value of current in secondary coil compared to primary coil is
X-rays are
The critical angle for total internal reflection of a ray from any medium to vacuum is 30\(^{\circ}\). Then velocity of light in the medium will be
Describe the two shortcomings of Bohr model of atom.
In a vertically upwards magnetic field \(\vec{B}\), a positively charged particle is projected horizontally eastwards. What will be the direction of force on the particle?
The coefficient of reflection for total internal reflection will be
The final image formed by a terrestrial telescope is
A spherical mirror is immersed in water. Its focal length will
The value of electric potential at a distance r from a point charge is
The relation between the drift velocity (\(V_d\)) and applied electric field (E) of a conductor is
64 identical drops each of capacity 5 µF combine to form a big drop. What will be the capacity of the big drop?
What is mainly measured by potentiometer?