Topics
Electric Charges and Fields
- Electric Charge
- Conductors and Insulators
- Properties of Electric Charge
- Coulomb’s Law
- Forces between Multiple Charges
- Electric Field
- Electric Field Due to a System of Charges
- Physical Significance of Electric Field
- Electric Field Lines
- Electric Flux
- Electric Dipole
- Dipole in a Uniform External Field
- Continuous Charge Distribution
- Gauss’s Law
- Application of Gauss' Law
Electrostatics
Current Electricity
Electrostatic Potential and Capacitance
- Electric Potential and Potential Energy
- Electrostatic Potential
- Electric Potential Due to a Point Charge
- Potential Due to an Electric Dipole
- Potential due to a System of Charges
- Equipotential Surfaces
- Relation Between Electric Field and Electrostatic Potential
- Potential Energy of a System of Charges
- Potential Energy of a Single Charge
- Potential Energy of a System of Two Charges in an External Field
- Potential Energy of a Dipole in an External Field
- Electrostatics of Conductors
- Dielectrics and Polarisation
- Capacitors and Capacitance
- The Parallel Plate Capacitor
- Effect of Dielectric on Capacitance
- Combination of Capacitors
- Energy Stored in a Charged Capacitor
Magnetic Effects of Current and Magnetism
Current Electricity
- Electric Current
- Electric Currents in Conductors
- Ohm's Law
- Drift of Electrons and the Origin of Resistivity
- Mobility of Electrons
- Limitations of Ohm’s Law
- Resistivity of Various Materials
- Temperature Dependence of Resistivity
- Electrical Energy and Power in Conductors
- Cells, EMF, and Internal Resistance
- Cells in Series and in Parallel
- Kirchhoff’s Laws
- Wheatstone Bridge
Electromagnetic Induction and Alternating Currents
Moving Charges and Magnetism
- Electromagnetism
- Magnetic force
- Motion in a Magnetic Field
- Magnetic Field Due to a Current-carrying Conductor: Biot-savart's Law
- Applications of Biot-Savart's Law > Magnetic Field at the Axis of a Circular Current-carrying Loop
- Ampere’s Circuital Law
- Solenoid
- Force Between Two Parallel Currents (Ampere’s Law)
- Torque on a Rectangular Current Loop in a Uniform Magnetic Field
- Circular Current Loop as a Magnetic Dipole
- Moving Coil Galvanometer
- Kirchhoff’s Laws
Magnetism and Matter
Electromagnetic Waves
Electromagnetic Induction
Optics
Dual Nature of Radiation and Matter
Alternating Current
Electromagnetic Waves
- Introduction to Electromagnetic Waves
- Displacement Current
- Sources of Electromagnetic Waves
- Nature of Electromagnetic Waves
- Electromagnetic Spectrum
- Definition and Characteristics of Electromagnetic Waves
Atoms and Nuclei
Electronic Devices
Ray Optics and Optical Instruments
- Ray Optics Or Geometrical Optics
- Reflection of Light by Spherical Mirrors
- Sign Convention for Reflection by Spherical Mirrors
- Focal Length of Spherical Mirrors
- Mirror Equation of Spherical Mirrors
- Refraction of Light
- Total Internal Reflection
- Applications of Total Internal Reflection
- Refraction at a Spherical Surfaces
- Refraction by a Lens
- Power of a Lens
- Combined Focal Length of Two Thin Lenses in Contact
- Refraction Through a Prism
- Introduction to Optical Instruments
- Microscope and it’s types
- Telescope
Wave Optics
- Introduction to Wave Optics
- Huygens Principle
- Refraction of a Plane Wave
- Refraction at a Rarer Medium
- Reflection of a Plane Wave by a Plane Surface
- Coherent and Incoherent Addition of Waves
- Interference of Light Waves and Young’s Experiment
- Diffraction of Light
- The Single Slit
- Seeing the Single Slit Diffraction Pattern
- Polarisation of Light
Communication Systems
Dual Nature of Radiation and Matter
- Understanding Dual Nature of Radiation and Matter
- Electron Emission
- Photoelectric Effect - Hertz’s Observations
- Photoelectric Effect - Hallwachs’ and Lenard’s Observations
- Experimental Study of Photoelectric Effect
- Effects of Intensity and Frequency on Photocurrent
- Photoelectric Effect and Wave Theory of Light
- Einstein’s Photoelectric Equation: Energy Quantum of Radiation
- Particle Nature of Light: The Photon
- Wave Nature of Matter
The Special Theory of Relativity
Atoms
Nuclei
Semiconductor Electronics - Materials, Devices and Simple Circuits
Communication Systems
- Detection of Amplitude Modulated Wave
- Production of Amplitude Modulated Wave
- Basic Terminology Used in Electronic Communication Systems
- Sinusoidal Waves
- Modulation and Its Necessity
- Amplitude Modulation (AM)
- Need for Modulation and Demodulation
- Satellite Communication
- Propagation of EM Waves
- Bandwidth of Transmission Medium
- Bandwidth of Signals
The Special Theory of Relativity
- The Special Theory of Relativity
- The Principle of Relativity
- Maxwell'S Laws
- Kinematical Consequences
- Dynamics at Large Velocity
- Energy and Momentum
- The Ultimate Speed
- Twin Paradox
Estimated time: 8 minutes
CBSE: Class 12
Introduction
When the study of nuclei goes beyond natural radioactive decay and includes reactions produced by bombarding nuclei with particles such as protons, neutrons, and alpha particles, new nuclear possibilities emerge.
One of the most important neutron-induced nuclear reactions is fission.
CBSE: Class 12
Definition: Nuclear Fission
Nuclear fission is a neutron-induced nuclear reaction in which a heavy nucleus, such as uranium-235, breaks into two intermediate-mass nuclear fragments.
CBSE: Class 12
Main Fission Reaction
When uranium-235 is bombarded with a neutron, it first forms uranium-236 and then splits into two lighter nuclei with the release of neutrons.
\[_0^1n+_{92}^{235}U\to_{92}^{236}U\to_{56}^{144}Ba+_{36}^{89}Kr+3_0^1n\]
This is one example of a fission reaction.
CBSE: Class 12
Other Possible Fission Products
The same neutron-induced reaction can also produce other pairs of intermediate-mass fragments.
\[_0^1n+_{92}^{235}U\to_{92}^{236}U\to_{51}^{133}Sb+_{41}^{99}Nb+4_0^1n\]
Another example is:
\[_0^1n+_{92}^{235}U\to_{54}^{140}Xe+_{38}^{94}Sr+2_0^1n\]
Important Observation
The same uranium nucleus can split into different pairs of intermediate-mass fragments.
CBSE: Class 12
Outcomes of Nuclear Fission
- The fragment products formed during fission are radioactive nuclei.
- These radioactive nuclei emit beta particles in succession to achieve stable end products.
- The disintegration energy in fission events first appears as the kinetic energy of the fragments and neutrons.
- Eventually, this energy is transferred to the surrounding matter and appears as heat.
CBSE: Class 12
Energy Released in Fission
The energy released, or Q value, in the fission reaction of nuclei like uranium is of the order of 200 MeV per fissioning nucleus.
Estimation of Energy Release
Consider a nucleus with mass number 240 breaking into two fragments, each with mass number 120.
- Binding energy per nucleon for the nucleus with A = 240 is about 7.6 MeV.
- Binding energy per nucleon for each fragment with A = 120 is about 8.5 MeV.
- Therefore, the gain in binding energy per nucleon is about 0.9 MeV.
- Hence, the total gain in binding energy is: 240 × 0.9 = 216 MeV
So, the total gain in binding energy is about 216 MeV.
CBSE: Class 12
Applications
- Nuclear Reactors: The source of energy in nuclear reactors, which produce electricity, is nuclear fission.
- Atom Bomb: The enormous energy released in an atom bomb comes from uncontrolled nuclear fission.
