List of top Questions asked in CBSE CLASS XII- 2025

Define 'emf' of a cell. Derive expression for the equivalent emf and the equivalent internal resistance of two cells connected in series.

In a Young's double-slit experiment with monochromatic light of wavelength 600 nm, and slit separation of 2 mm, fringes are observed on a screen at some distance. Calculate the change in fringe width if the screen is moved towards the slits by 10 cm.

Write Coulomb's law in vector form. Two point charges \(q_1 = 10\,\mu\text{C}\) and \(q_2 = 20\,\mu\text{C}\) are located, respectively, in the x-y plane at points \((0, 0)\) and \((3\,\text{cm}, 4\,\text{cm})\). Find (i) the magnitude of the force exerted on \(q_2\) by \(q_1\), and (ii) the angle that the force makes with the x-axis.

Monochromatic light of frequency \(7.0 \times 10^{14}\) Hz is produced by a laser. The power emitted is 21 mW. Calculate (i) the energy of a photon in the light beam, and (ii) the number of photons per second, on an average, emitted by the source.

Consider two long, straight, parallel conductors A and B separated by a distance \(d\). They carry steady current \(I\) in the same direction. The force acting on unit length of conductor B due to conductor A is:

Welders wear special glass goggles or face masks with glass windows to protect their eyes from:

In Bohr model of the hydrogen atom, the potential energy of electron in the ground state is:

The electric field due to an infinitely long, straight, uniformly and positively charged wire at a point at distance \(r\) from the wire is:

"The limited availability of agricultural land as well as its deterioration in quality is a very serious concern today." Examine the statement in the context of land degradation.

"Noise pollution has become a serious concern in recent years." Examine the statement by giving suitable examples.

For our landlocked neighbouring countries like Nepal and Bhutan, the port facilities are extended by which one of the following ports ?

Analyse the socio-economic and historical factors influencing the spatial distribution of population in India.

Read the following statements regarding rainwater harvesting carefully and choose the correct option.

It is a method to capture and store rainwater for various uses.
Groundwater aquifers are aimed to recharge by this method.
Rainwater harvesting increases water availability for use.
Storing water by dam construction is very widely used in India for rainwater harvesting.

Differentiate between cottage and small scale manufacturing in the world with suitable examples.

"Indian ports are handling large volumes of domestic as well as overseas trade." Examine the statement.

Two statements are given below. They are Assertion (A) and Reason (R). Read both the statements carefully and choose the correct option.

Assertion (A) : The decades of 1921 – 1951 are referred to as the period of steady growth of population in India.

Reason (R) : Improvement in health and sanitation; lowering mortality rate associated with high birth rate caused the population to grow fast.

Health, education, food, water supply, sanitation, and housing are the focus of which one of the following approaches of human development ?

Arrange the following towns of India, based on their evolution from the earliest to the newest order and choose the correct option.

Jamshedpur
Bhubaneswar
Varanasi
Hyderabad

Examine the sources of air pollution and its impact on human health.

Examine the problems faced by the slum dwellers in Indian cities.

Differentiate between agro-based and mineral-based industries in the world, by giving suitable examples.

Analyse the growth of India's population from 1981 to present day.

Examine the role of air transport of India in international trade.

Which of the following statements regarding watershed management are correct ? Choose the correct option.

Watershed management refers to efficient management and conservation of surface and groundwater.
It involves the prevention of surface runoff and recharge of groundwater.
The success of watershed management largely depends upon community participation.
The project is executed by the office of the Chief Ministers of respective states.

Which one of the following sea ports is located at the head of Vembanad Kayal ?