NEET 2026 Physics Formulas

Cheatsheet Content

### Basic Maths #### Trigonometry - $\sin^2\theta + \cos^2\theta = 1$ - $1 + \tan^2\theta = \sec^2\theta$ - $1 + \cot^2\theta = \csc^2\theta$ - $\sin2\theta = 2\sin\theta\cos\theta$ - $\cos2\theta = 1 - 2\sin^2\theta = 2\cos^2\theta - 1$ #### Small Angle Approximation - $\sin\theta \approx \theta$ - $\tan\theta \approx \theta$ - $\cos\theta \approx 1$ ### Vectors - **Resultant:** $R = \sqrt{A^2 + B^2 + 2AB\cos\theta}$ - **Dot Product:** $\vec{A} \cdot \vec{B} = AB\cos\theta$ - **Cross Product:** $|\vec{A} \times \vec{B}| = AB\sin\theta$ - **Components:** - $A_x = A\cos\theta$ - $A_y = A\sin\theta$ ### Units & Dimensions - **Velocity:** $[LT^{-1}]$ - **Acceleration:** $[LT^{-2}]$ - **Force:** $[MLT^{-2}]$ - **Energy:** $[ML^2T^{-2}]$ - **Power:** $[ML^2T^{-3}]$ ### Kinematics #### Equations of Motion - $v = u + at$ - $s = ut + \frac{1}{2}at^2$ - $v^2 = u^2 + 2as$ #### Projectile Motion - **Time of Flight:** $T = \frac{2u\sin\theta}{g}$ - **Range:** $R = \frac{u^2\sin2\theta}{g}$ - **Maximum Height:** $H = \frac{u^2\sin^2\theta}{2g}$ ### Laws of Motion - **Newton's Second Law:** $F = ma$ - **Weight:** $W = mg$ - **Friction:** $f = \mu N$ - **Hooke's Law (Spring Force):** $F = -kx$ ### Work, Energy, Power - **Work Done:** $W = FS\cos\theta$ - **Kinetic Energy:** $KE = \frac{1}{2}mv^2$ - **Potential Energy (Gravitational):** $PE = mgh$ - **Power:** $P = Fv$ - **Energy Conservation:** $KE + PE = \text{constant}$ ### Rotation - **Torque:** $\tau = rF\sin\theta$ - **Angular Momentum:** $L = I\omega$ - **Rotational Kinetic Energy:** $KE = \frac{1}{2}I\omega^2$ #### Moment of Inertia - **Ring:** $MR^2$ - **Disc:** $\frac{1}{2}MR^2$ - **Solid Sphere:** $\frac{2}{5}MR^2$ ### Gravitation - **Gravitational Force:** $F = \frac{GMm}{r^2}$ - **Acceleration due to Gravity:** $g = \frac{GM}{R^2}$ - **Gravitational Potential Energy:** $U = -\frac{GMm}{r}$ - **Escape Velocity:** $v_e = \sqrt{\frac{2GM}{R}}$ ### Properties of Matter #### Fluids - **Pressure:** $P = \frac{F}{A}$ - **Pressure in fluid column:** $P = \rho gh$ - **Buoyant Force:** $F_B = \rho gV$ #### Surface Tension - $T = \frac{F}{L}$ #### Viscosity - **Viscous Force:** $F = \eta A \frac{dv}{dx}$ ### Thermodynamics - **Ideal Gas Law:** $PV = nRT$ - **First Law of Thermodynamics:** $Q = \Delta U + W$ - **Efficiency of Heat Engine:** $\eta = \frac{W}{Q_1}$ ### Oscillations (SHM) - **Displacement:** $x = A\sin\omega t$ - **Velocity:** $v = \omega\sqrt{A^2 - x^2}$ - **Acceleration:** $a = -\omega^2 x$ #### Time Period - **Spring-Mass System:** $T = 2\pi\sqrt{\frac{m}{k}}$ - **Angular Frequency:** $\omega = \sqrt{\frac{k}{m}}$ ### Waves - **Wave Speed:** $v = f\lambda$ - **Frequency:** $f = \frac{1}{T}$ - **Speed of Transverse Wave on String:** $v = \sqrt{\frac{T}{\mu}}$ #### Doppler Effect - $f' = f \left(\frac{v \pm v_o}{v \mp v_s}\right)$ ### Electrostatics - **Coulomb's Law:** $F = \frac{kq_1q_2}{r^2}$ - **Electric Field:** $E = \frac{kq}{r^2}$ - **Electric Potential:** $V = \frac{kq}{r}$ - **Electric Potential Energy:** $U = \frac{kq_1q_2}{r}$ ### Capacitors - **Capacitance:** $C = \frac{Q}{V}$ - **Parallel Plate Capacitor:** $C = \frac{\epsilon_0 A}{d}$ #### Energy Stored - $U = \frac{1}{2}CV^2$ ### Current Electricity - **Ohm's Law:** $V = IR$ - **Power:** $P = VI = I^2R = \frac{V^2}{R}$ - **Drift Velocity:** $v_d = \frac{eE\tau}{m}$ - **Current:** $I = nqAv_d$ ### Magnetism - **Force on moving charge:** $F = qvB\sin\theta$ - **Force on current-carrying wire:** $F = BIL\sin\theta$ - **Magnetic Field (long straight wire):** $B = \frac{\mu_0 I}{2\pi r}$ ### EMI (Electromagnetic Induction) - **Faraday's Law:** $\epsilon = -\frac{d\Phi}{dt}$ - **Magnetic Flux:** $\Phi = BA\cos\theta$ - **Self-Induced EMF:** $\epsilon = -L\frac{di}{dt}$ ### AC (Alternating Current) - **Instantaneous Voltage:** $V = V_0\sin\omega t$ - **RMS Current:** $I_{rms} = \frac{I_0}{\sqrt{2}}$ - **RMS Voltage:** $V_{rms} = \frac{V_0}{\sqrt{2}}$ #### Reactance - **Inductive Reactance:** $X_L = \omega L$ - **Capacitive Reactance:** $X_C = \frac{1}{\omega C}$ ### Ray Optics - **Mirror Formula:** $\frac{1}{f} = \frac{1}{v} + \frac{1}{u}$ - **Lens Formula:** $\frac{1}{f} = \frac{1}{v} - \frac{1}{u}$ - **Magnification:** $m = \frac{v}{u}$ ### Wave Optics - **Fringe Width:** $\beta = \frac{\lambda D}{d}$ - **Path Difference (constructive):** $\Delta x = n\lambda$ ### Modern Physics - **Photon Energy:** $E = hf$ - **De Broglie Wavelength:** $\lambda = \frac{h}{p}$ - **Mass-Energy Equivalence:** $E = mc^2$ ### Semiconductors - **Current (general):** $I = nqAv_d$ - **V-I Characteristics (diode)** - **Logic Gates:** AND, OR, NOT