INJSO Revision Cheatsheet

Cheatsheet Content

### Mechanics - **Kinematics:** - Equations of motion: $v = u + at$, $s = ut + \frac{1}{2}at^2$, $v^2 = u^2 + 2as$ - Uniform circular motion: centripetal acceleration and force - Projectile motion: horizontal and vertical components, range, max height - **Newton's Laws of Motion:** - First Law: Inertia, frames of reference - Second Law: $F = ma$, free-body diagrams - Third Law: Action-reaction pairs, normal force, tension, friction - Impulse ($I = F\Delta t$) and momentum ($p = mv$): Conservation of momentum, elastic and inelastic collisions - **Work, Energy, Power:** - Work done: $W = Fd\cos\theta$, work-energy theorem - Kinetic energy: $KE = \frac{1}{2}mv^2$ - Potential energy: $PE = mgh$ (gravitational), $PE = \frac{1}{2}kx^2$ (spring) - Conservation of mechanical energy (conservative forces) - Power: $P = \frac{W}{t} = Fv$ - **Rotational Motion:** - Angular displacement, velocity, acceleration - Torque: $\tau = rF\sin\theta$ - Moment of inertia (basic concepts) - Angular momentum: $L = I\omega$, conservation of angular momentum - **Gravitation:** - Newton's Law of Universal Gravitation: $F = G\frac{m_1m_2}{r^2}$ - Gravitational field strength: $g = G\frac{M}{r^2}$ - Orbital motion: escape velocity, orbital velocity (qualitative understanding) - **Simple Harmonic Motion (SHM):** - Definition, conditions for SHM - Pendulum, mass-spring system - Period, frequency, amplitude ### Fluids - **Properties of Fluids:** Density ($\rho = \frac{m}{V}$), pressure ($P = \frac{F}{A}$) - **Fluid Statics:** - Pressure variation with depth: $P = P_0 + \rho gh$ - Pascal's Principle: hydraulic lift applications - Archimedes' Principle: Buoyant force $F_B = \rho_{fluid} V_{displaced} g$, flotation - **Fluid Dynamics (basic concepts):** - Streamline flow, turbulent flow - Continuity equation (qualitative) - Bernoulli's Principle (qualitative applications) - Viscosity, surface tension (qualitative) ### Thermal Physics - **Heat and Temperature:** - Temperature scales: Celsius, Fahrenheit, Kelvin conversions - Thermal expansion: linear, area, volume expansion coefficients - Specific heat capacity: $Q = mc\Delta T$, calorimetry - Latent heat: $Q = mL$ (fusion, vaporization) - **Heat Transfer:** - Conduction: thermal conductivity - Convection: natural and forced - Radiation: black body radiation, Stefan-Boltzmann Law (qualitative) - **Thermodynamics:** - Zeroth Law: thermal equilibrium - First Law: $\Delta U = Q - W$ (work done by/on the system) - Second Law: entropy, heat engines, refrigerators (qualitative concepts) - Ideal gas equation: $PV = nRT$ ### Waves and Sound - **Wave Properties:** - Transverse and longitudinal waves - Wave speed: $v = f\lambda$ - Amplitude, wavelength, frequency, period - Superposition principle: interference, diffraction (qualitative) - **Sound Waves:** - Production and propagation of sound - Speed of sound in different media - Characteristics of sound: pitch (frequency), loudness (amplitude), quality (waveform) - Reflection of sound: echoes - Doppler effect (conceptual understanding) ### Optics - **Nature of Light:** Wave-particle duality (conceptual) - **Reflection:** - Law of Reflection - Plane mirrors: image formation, characteristics - Spherical mirrors: concave and convex, ray diagrams, mirror formula ($\frac{1}{f} = \frac{1}{u} + \frac{1}{v}$), magnification - **Refraction:** - Snell's Law: $n_1\sin\theta_1 = n_2\sin\theta_2$ - Refractive index - Real and apparent depth - Total Internal Reflection: critical angle, applications (optical fibers) - Lenses: converging and diverging, ray diagrams, lens formula ($\frac{1}{f} = \frac{1}{v} - \frac{1}{u}$), magnification - Dispersion of light: prism, spectrum - **Optical Instruments:** - Human eye: structure, accommodation, defects (myopia, hypermetropia) and correction - Simple microscope, compound microscope, telescope (basic working principles) ### Electricity - **Electrostatics:** - Electric charge: properties, conservation, quantization - Coulomb's Law: $F = k\frac{q_1q_2}{r^2}$ - Electric field: concept, field lines - Electric potential and potential difference - **Current Electricity:** - Electric current: $I = \frac{Q}{t}$ - Ohm's Law: $V = IR$ - Resistance: factors affecting resistance, resistivity ($\rho$), $R = \rho\frac{L}{A}$ - Series and parallel combinations of resistors - Electrical energy and power: $P = VI = I^2R = \frac{V^2}{R}$ - Kirchhoff's Laws (basic application to simple circuits) - Electromotive force (EMF) and internal resistance - **Capacitance (basic):** - Concept of capacitor, capacitance - Energy stored in a capacitor (qualitative) ### Magnetism - **Magnetic Fields:** - Properties of magnets, magnetic poles - Magnetic field lines - Earth's magnetic field - **Magnetic Effects of Current:** - Oersted's experiment - Magnetic field due to a straight current-carrying wire, circular loop, solenoid (qualitative) - Force on a current-carrying conductor in a magnetic field: $F = BIL\sin\theta$ - Force between two parallel current-carrying wires (qualitative) - Torque on a current loop (motors - principle) - **Electromagnetic Induction:** - Faraday's Law of Electromagnetic Induction: induced EMF, magnetic flux (qualitative) - Lenz's Law: direction of induced current - AC generator (principle) - Transformers: step-up, step-down (qualitative, ideal transformer equation) ### Modern Physics (Basic Concepts) - **Atomic Structure:** - Rutherford's model, Bohr's model of hydrogen atom (energy levels, spectral series - conceptual) - X-rays: production and properties (qualitative) - **Nuclear Physics:** - Atomic nucleus: protons, neutrons, isotopes - Radioactivity: alpha, beta, gamma decay (properties, half-life - conceptual) - Nuclear fission and fusion (basic principles, energy release) - **Photoelectric Effect:** - Basic phenomenon, Einstein's explanation (qualitative) ### Experimental Skills & Data Analysis - **Laboratory Safety:** General rules, handling apparatus and chemicals specific to physics experiments. - **Measurement:** - Units (SI system), conversion - Significant figures, precision, accuracy, errors (random, systematic) - Measuring instruments: Vernier caliper, screw gauge, stopwatch, ammeter, voltmeter, thermometer, spring balance, physical balance. - **Data Interpretation:** - Reading and plotting graphs (linearization techniques) - Finding slope and intercept, interpreting their physical meaning - Error analysis (basic propagation of errors, percentage error) - **Experimental Design:** - Formulating hypotheses, identifying variables (independent, dependent, controlled) - Setting up experiments, taking readings, repeating measurements - Drawing conclusions based on experimental data