A physics formula is a mathematical equation that expresses the relationship between physical quantities like force, energy, velocity, and charge. Physics equations translate the laws of science into a form you can use to solve numerical problems. Every CBSE, JEE, and NEET question in physics requires you to know and apply the right formula at the right time.
If you have a physics exam coming up, this page gives you physics formulas by class and topic. It covers Class 9 to 12 formulas, key constants, exam-focused formula groups, and solved examples. Use it for quick revision before CBSE board exams, JEE, and NEET.
Key Takeaways
| What This Page Covers |
Details |
| Classes |
9, 10, 11, 12 |
| Chapters |
Mechanics, Thermodynamics, Optics, Electricity, Modern Physics |
| Exam Coverage |
CBSE Board, JEE Main, JEE Advanced, NEET |
| Physics Constants |
Yes, including Planck, Boltzmann, Avogadro and 10 more |
| Solved Examples |
Yes, 10 worked problems |
| Download the Physics Formulas PDF |
Available |
All Physics Formulas for Quick Revision
Students score better when they identify the right formula fast. This table gives you the most important physics formulas in one place. Use it as a quick revision sheet before exams.
| Formula Name |
Formula |
| Acceleration |
a = (v – u) / t |
| Newton's Second Law |
F = m × a |
| Work Done |
W = F × d × cos θ |
| Kinetic Energy |
KE = ½ × m × v² |
| Potential Energy |
PE = m × g × h |
| Power |
P = W / t |
| Pressure |
P = F / A |
| Density |
ρ = m / V |
| Ohm's Law |
V = I × R |
| Gravitational Force |
F = G(m₁ × m₂) / R² |
| Wavelength |
λ = v / f |
| Refractive Index |
n = c / v |
| Friction Force |
f = μ × N |
| Pendulum Time Period |
T = 2π√(L / g) |
For chapter-wise formulas, scroll to your class below or jump to JEE Physics formulas or NEET Physics formulas.
Physics Formulas for Class 9
Class 9 is where the foundation is built. These basic physics formulas appear directly in board exams and set the base for everything in Class 11 and 12.
Motion Formulas Class 9
| Formula Name |
Formula |
| Average Speed |
s = d / t |
| Acceleration |
a = (v – u) / t |
| First Equation of Motion |
v = u + at |
| Second Equation of Motion |
s = ut + ½at² |
| Third Equation of Motion |
v² = u² + 2as |
Force, Work and Energy Class 9
| Formula Name |
Formula |
| Newton's Second Law |
F = ma |
| Momentum |
p = mv |
| Work Done |
W = F × d × cos θ |
| Kinetic Energy |
KE = ½mv² |
| Potential Energy |
PE = mgh |
| Power |
P = W / t |
Gravitation Class 9
| Formula Name |
Formula |
| Universal Gravitation |
F = G(m₁m₂) / r² |
| Weight |
W = mg |
| Acceleration due to Gravity |
g = GM / R² |
Physics Formulas for Class 10
Physics formulas for Class 10 mainly come from Electricity and Light. These formulas appear often in board exam numericals. Students should revise them together with units and sign conventions.
Electricity Formulas Class 10
| Formula Name |
Formula |
| Ohm's Law |
V = IR |
| Resistance in Series |
R = R₁ + R₂ + R₃ |
| Resistance in Parallel |
1/R = 1/R₁ + 1/R₂ + 1/R₃ |
| Electric Power |
P = VI = I²R = V²/R |
| Electric Energy |
E = P × t |
Light: Reflection and Refraction Formulas Class 10
| Formula Name |
Formula |
| Mirror Formula |
1/f = 1/v + 1/u |
| Magnification (Mirror) |
m = –v / u |
| Snell's Law |
n₁ sin θ₁ = n₂ sin θ₂ |
| Refractive Index |
n = c / v |
| Lens Formula |
1/f = 1/v – 1/u |
| Lens Power |
P = 1 / f (metres) |
Practise these with Extramarks Class 10 Science important questions mapped to your board exam pattern.
Physics Formulas for Class 11
Physics formulas for Class 11 build the base for Class 12 and competitive exams. Topics like kinematics, laws of motion, work, energy, and thermodynamics need regular revision.
Kinematics Formulas Class 11
| Formula Name |
Formula |
| Velocity |
v = u + at |
| Displacement |
s = ut + ½at² |
| Velocity–Displacement |
v² = u² + 2as |
| Projectile Range |
R = u² sin 2θ / g |
| Maximum Height |
H = u² sin²θ / 2g |
| Time of Flight |
T = 2u sin θ / g |
Laws of Motion and Friction Class 11
| Formula Name |
Formula |
| Newton's Second Law |
F = ma |
| Momentum |
p = mv |
| Impulse |
J = F × t |
| Friction Force |
f = μN |
Work, Energy and Power Class 11
| Formula Name |
Formula |
| Work–Energy Theorem |
W = ΔKE |
| Elastic Collision |
m₁u₁ + m₂u₂ = m₁v₁ + m₂v₂ |
| Spring Potential Energy |
PE = ½kx² |
Rotational Motion Class 11
| Formula Name |
Formula |
| Torque |
τ = r × F × sin θ |
| Angular Momentum |
L = I × ω |
| Moment of Inertia |
I = mr² |
Thermodynamics Formulas Class 11
| Formula Name |
Formula |
| First Law of Thermodynamics |
ΔU = Q – W |
| Ideal Gas Law |
PV = nRT |
| Specific Heat |
Q = mcΔT |
| Latent Heat |
Q = mL |
Physics Formulas for Class 12
Physics formulas for class 12 are tested in CBSE boards, JEE, and NEET. Electrostatics, current electricity, optics, and modern physics need good formula recall. Students should revise formulas with solved questions.
Electrostatics Formulas Class 12
| Formula Name |
Formula |
| Coulomb's Law |
F = k(q₁q₂) / r² |
| Electric Field |
E = F / q |
| Electric Potential |
V = kq / r |
| Capacitance |
C = Q / V |
| Energy in Capacitor |
U = ½CV² |
Current Electricity Class 12
| Formula Name |
Formula |
| Ohm's Law |
V = IR |
| Wheatstone Bridge |
P/Q = R/S |
| Resistivity |
R = ρL / A |
Electromagnetic Induction Class 12
| Formula Name |
Formula |
| Magnetic Force |
F = qvB sin θ |
| Magnetic Flux |
Φ = BA cos θ |
| Faraday's Law |
e = –N(dΦ / dt) |
Optics Formulas Class 12
| Formula Name |
Formula |
| Lens Maker's Formula |
1/f = (n–1)(1/R₁ – 1/R₂) |
| Refractive Index |
n = sin i / sin r |
| Diffraction Condition |
a sin θ = mλ |
Modern Physics Formulas Class 12
| Formula Name |
Formula |
| Photoelectric Effect |
KE = hf – φ |
| de Broglie Wavelength |
λ = h / mv |
| Mass–Energy Equivalence |
E = mc² |
| Radioactive Decay |
N = N₀ e^(–λt) |
| Half-Life |
T½ = 0.693 / λ |
Important Physics Constants Values
Physics constants help you solve numerical questions accurately. Students should revise these values with symbols and SI units. Keep this list with your physics equation sheet.
| Constant |
Symbol |
Value |
| Planck's Constant |
h |
6.63 × 10⁻³⁴ J·s |
| Speed of Light |
c |
3 × 10⁸ m/s |
| Gravitational Constant |
G |
6.67 × 10⁻¹¹ N·m²/kg² |
| Charge of Electron |
e |
1.6 × 10⁻¹⁹ C |
| Mass of Electron |
mₑ |
9.1 × 10⁻³¹ kg |
| Mass of Proton |
mₚ |
1.67 × 10⁻²⁷ kg |
| Boltzmann Constant |
k |
1.38 × 10⁻²³ J/K |
| Avogadro's Number |
Nₐ |
6.023 × 10²³ mol⁻¹ |
| Molar Gas Constant |
R |
8.314 J/(mol·K) |
| Faraday Constant |
F |
96485 C/mol |
| Permittivity of Vacuum |
ε₀ |
8.85 × 10⁻¹² F/m |
| Stefan–Boltzmann Constant |
σ |
5.67 × 10⁻⁸ W/(m²·K⁴) |
Want a printable revision sheet? Download the complete physics formulas PDF with class-wise tables, constants, and exam-focused formula groups.
Physics Formulas for JEE Main and Advanced
JEE Physics tests formula application under time pressure. Students should revise formulas from high-weightage chapters and practise mixed numericals regularly.
Highest-weightage chapters for JEE Physics:
These chapters usually need the most formula practice for JEE Physics:
- Electrostatics and Current Electricity
- Optics: Ray and Wave
- Kinematics and Laws of Motion
- Modern Physics
Must-know JEE Physics formulas:
| Topic |
Formula |
| Projectile Range |
R = u² sin 2θ / g |
| Escape Velocity |
v = √(2gR) |
| Coulomb's Law |
F = kq₁q₂ / r² |
| Photoelectric Effect |
KE = hf – φ |
| de Broglie Wavelength |
λ = h / mv |
| Lens Maker's Formula |
1/f = (n–1)(1/R₁ – 1/R₂) |
Practise these with Extramarks JEE Physics Advanced Physics important questions designed around the actual JEE paper pattern.
Physics Formulas for NEET
NEET Physics needs fast formula recall and accurate application. Mechanics, optics, thermodynamics, and modern physics need regular revision. Students should practise formulas with time-bound questions.
Highest-weightage chapters for NEET Physics:
- Mechanics: Motion, Laws of Motion, Work and Energy
- Optics: Lens formula, refraction, optical instruments
- Modern Physics: Radioactivity and nuclear physics
- Thermodynamics
Must-know NEET Physics formulas:
| Topic |
Formula |
| Acceleration |
a = (v – u) / t |
| Lens Formula |
1/f = 1/v – 1/u |
| Ideal Gas Law |
PV = nRT |
| Radioactive Decay |
N = N₀ e^(–λt) |
| Kinetic Energy |
KE = ½mv² |
| Refractive Index |
n = c / v |
Use Extramarks NEET Physics preparation resources to practise formula application with past paper questions sorted by chapter and difficulty.
How to Memorise Physics Formulas
Students remember formulas better when they understand the concept first. These steps help you revise formulas for boards and entrance exams.
- Understand the concept first. Every physics formula describes a real relationship. Know what each variable represents before writing the equation.
- Derive the formula when possible. Deriving a formula once builds more retention than memorising it ten times. It helps you reconstruct it if you blank out.
- Group formulas by chapter. Learn all kinematics formulas together. Learn all optics formulas together. Isolated formulas are harder to recall during exams.
- Write and revise daily. Put 5 to 10 formulas on a revision card each morning. Test yourself before sleeping.
- Solve questions right after revision. After learning a formula, solve 2 to 3 numerical problems using it right away. This is how the formula gets stored as usable knowledge.
- Connect formulas to real situations. F = ma explains why airbags deploy fast. PE = mgh explains why water towers are built tall. These connections stay in memory far longer than plain equations.
SI Units Used in Physics Formulas
SI units keep formula-based calculations consistent.
Always convert values to metres, kilograms, seconds, and amperes before substitution.
Mixed units often lead to wrong answers in numerical questions.
Solved Examples Using Physics Formulas
These examples show how to apply physics formulas step by step in common exam questions.
Q1. A car goes from 0 to 60 m/s in 3 seconds. Find its acceleration.
Formula: a = (v - u) / t
Substitution: a = (60 - 0) / 3
Answer: 20 m/s²
Q2. Find the kinetic energy of a 4 kg object moving at 5 m/s.
Formula: KE = 1/2 mv²
Substitution: KE = 1/2 x 4 x 5²
Answer: 50 J
Q3. A 10 kg body is lifted to a height of 5 m. Find the potential energy stored.
Formula: PE = mgh
Substitution: PE = 10 x 10 x 5
Answer: 500 J
Q4. A circuit has 12 V across a 4 ohm resistor. Find the current.
Formula: I = V / R
Substitution: I = 12 / 4
Answer: 3 A
Q5. A pendulum is 1 m long. Find its time period. Take g = 10 m/s².
Formula: T = 2pi root(L / g)
Substitution: T = 2pi root(1 / 10)
Answer: 1.99 s
Q6. A person has a mass of 50 kg. Find the weight on the Moon if g = 1.6 m/s².
Formula: W = mg
Substitution: W = 50 x 1.6
Answer: 80 N
Q7. An object moves at 5 m/s and has kinetic energy of 100 J. Find its mass.
Formula: KE = 1/2 mv²
Substitution: 100 = 1/2 x m x 25
Answer: 8 kg
Q8. Find the resistance of a wire of length 0.5 m, area 2 x 10⁻⁶ m², and resistivity 1.6 x 10⁻⁸ ohm m.
Formula: R = rhoL / A
Substitution: R = (1.6 x 10⁻⁸ x 0.5) / (2 x 10⁻⁶)
Answer: 0.004 ohm
Q9. A car of mass 250 kg travels at 10 m/s. Find its kinetic energy.
Formula: KE = 1/2 mv²
Substitution: KE = 1/2 x 250 x 10²
Answer: 12,500 J
Q10. A substance absorbs 400 kcal of heat during a phase change. Its mass is 2 kg. Find the latent heat.
Formula: L = Q / m
Substitution: L = 400 / 2
Answer: 200 kcal/kg