Important Formulas for JEE Main 2021: Physics, Chemistry and Maths Formulas

Last updated on July 21st, 2021

Multiple sessions of JEE Main 2021 has given the students additional time and opportunity to prepare their best for the examination. If used wisely, this time can turn out to be highly beneficial. Students can revise some of the Important Formulas for JEE Main 2021 to scale up their knowledge and preparation.

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Latest: JEE Main 2021 May Session is postponed by NTA amid the surge in COVID-19 cases in India. NTA might conduct the exam in July-August. Read More

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• Revision is the most important aspect of preparing for any exam. Students can take our preparation tips for JEE Main 2021.
• Candidates can prepare flashcards, make a last-minute revision plan, revise all the important formulas of JEE Main Physics, Chemistry or Maths.
• Having memorized all the JEE Main Important Formulas will lead to the candidate acing the JEE Main 2021 with a good score.

Students can download this formulas page as a PDF by using the print option.

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How Do JEE Main Important Formulas Help?

It is very important for the students to compile their study material before starting the preparations. While preparing for the exam, make notes for the important formulas for each and every subject separately. These handy notes help in focusing on the concepts. The JEE Main important formulas can help candidates in various ways:

• It helps in saving time in the exam.
• Makes the calculations easier.
• Reduces the risk of mistakes.

Note: NTA has declared a new JEE Main exam pattern that adds a new Numeric value-based problem to each section.

Check – Subject-wise Formula Handbooks by Resonance

Important Formulas for JEE Main 2021

JEE Main Paper-1 is the most sought after paper among the 3. It consists of three sections, namely-

• Physics
• Chemistry
• Mathematics

The candidates can refer to the subject-wise JEE Main 2021 important formulas below.

Also Check-

• JEE Main Old Question Paper PDFs (with solutions)
• JEE Advanced 2021 Practice Papers

Important Formulas for JEE Main 2021 Physics

JEE Main Physics section is considered to be a tough section. One should be thorough with the Physics syllabus. When candidates prepare for JEE Main exam, they find Physics as the toughest section because of the long derivations. Let us look at some important formulas listed for JEE Main that will help in the efficient preparation of physics.

• The energy of electric dipole is given by U = – p.E.
• The energy of a magnetic dipole is U = – μ .B C.
• Electric Charge : Q = ± ne (e = 1.60218 × 10-29 C)
• SI unit of Electric Charge is Coulomb (C)
• Coulomb’s Law : Electrostatic Force (F) = k[q1q2/r2] and,
• In Vector Form :
  • →F=k(q1q2)×→r/r3
    • Where, q1 and q2 = Charges on the Particle,
    • r = Separation between them,
    • →r = Position Vector,
    • k = Constant = 14πϵ0=8.98755×109Nm2C2
• Electric Current :
  • The current at Time t : i=limΔt→0 ΔQ/Δt= dQ/dT
    • Where Δ Q and Δ T = Charges crosses an Area in time Δ T
    • SI unit of Current is Ampere (A) and 1A = 1 C/s
• Average current density:
  • →j=Δi/Δs
  • j=limΔs→0 Δi/Δs=di/dS ,
  • j=Δi/ΔScosθ
    • Where, Δ S = Small Area,
    • Δ i = Current through the Area Δ S,
    • P = Perpendicular to the flow of Charges,
    • θ = Angle Between the normal to the Area and the direction of the current.
• Kirchhoff’s Law:
  • Law of Conservation of Charge: I3 = I1 + I2

Resistance

• Resistivity : ρ(T)=ρ(T0)[1+α(T−T0)]
  • R (T) =R (T0) [1+α (T−T0)]
    • Where, ρ (T) and ρ (T0) = Resistivity at Temperature T and T0 respectively,
    • α = Constant for given material.

• Lorentz Force :
  • →F=q[→E+(→v×→B)]
    • Where, E = Electric Field,
    • B = Magnetic Field,
    • q = Charge of Particle,
    • v = Velocity of Particle.
• Magnetic Flux:
  • Magnetic Flux through Area dS = ϕ=→B⋅d → S= B⋅dS Cos θ
    • Where, d→S = Perpendicular vector to the surface and has a magnitude equal to are Ds,
    • →B = Magnetic Field at an element,
    • θ = Angle Between →B and d→S,
    • SI unit of Magnetic Flux is Weber (Wb).
• Straight line Equation of Motion (Constant Acceleration):
  • v=u+at
  • s=ut+1/2at2
  • 2as=v2−u2
• Gravitational Acceleration Equation of Motion:
  • Motion in Upward Direction:
    • v= u-gt
    • y=ut−1/2gt2
    • −2gy=v2−u2
  • Motion in Downward Direction:
    • v=u+gt
    • y=ut+1/2gt2
    • 2gy=v2−u2
• Projectile Equation of Motion:
  • Horizontal Range (R) = u2sin2θ/ g
  • Time of Flight (T) = 2uSinθ/ g
  • Maximum Height (H) = u2sin2θ/ 2
  • Where,
    • u = initial velocity,
    • v = final velocity,
    • a = constant acceleration,
    • t = time,
    • x = position of particle.

Laws of Gravity

• Universal Law of Gravitation:
  • Gravitational force →F=G[Mm/r2]^r
  • Where, M and m = Mass of two Objects,
    • r = separation between the objects,
    • ^r = unit vector joining two objects,
    • G = Universal Gravitational Constant
      • [G=6.67×10−11N⋅m2/Kg2]
• Work Done by Constant Force:
  • Work Done (W) = →F⋅→S=∣→F∣ ∣→S∣ cosθ,
    • Where, S = Displacement along a straight line,
    • F = applied force,
    • θ = Angle between S & F.
  • It is a scalar quantity and the Dimension of work is [M1 L2 T-2], SI unit of Work is the joule (J) and 1J=1N⋅m=Kg⋅m2/ s2
• Kinetic Friction:
  • fk = µk · N
  • Maximum Static Friction (Limiting Friction): fmax = µs · N,
    • Where, N = Normal Force,
    • µk = Coefficient of Kinetic Friction,
    • µs = Coefficient of Static Friction.
• Simple Harmonic Motion:
  • Force (F) = – k x and k = ω2 m
    • Where, k = Force Constant,
    • m = Mass of the Particle,
    • x = Displacement and ω2 = Positive Constant.
• Torque: The torque or vector moment or moment vector (M) of a force (F) about a point (P) is defined as:
  • M = r×F
  • Where, r is the vector from the point P to any point A on the line of action L of F.

Also Read | IIT Bombay: B.Tech in Engineering Physics Cut Off

Important Formulas for JEE Main 2021 Chemistry

Chemistry is considered an easy section comparatively. With the right preparation, maximum scores can be secured from this section. Let us take a look at JEE Main Chemistry Important Formulas List-

• T(K)= T(⁰C) + 273.15
• Molarity (M)= No. of Moles of Solutes/ Volume of Solution in Liters
• Unit: mole/ L
• Molality (m)=
  • No. of Moles of Solutes/ Mass of solvent in kg

• Molecular Mass= 2x vapor density
• Atomic number=
  • No. of protons in the nucleus = No. of electrons in the nucleus
• Mass number=
  • No. of protons + No. of neutrons C= vλ
• Boyle’s Law:
  • P1V1 = P2V2 (at constant T and n)
• Charles’s Law:
  • V1/ T1 = V2/ T2 (at constant P and n)
• Enthalpy:
  • H = U + pV
• First Law of Thermodynamics:
  • ΔU = q + W
• Ohm’s Law:
  • V = RI where, R = ρ ι/a

Faraday’s Laws

• Faraday’s First Law of Electrolysis:
  • M = Zit
    • M = mass of substance deposited
    • Z= Electrochemical Equivalent
    • I = current,
    • t= time
    • Z= Atomic Mass/ n x F
• Faraday’s Second Law of Electrolysis:
  • M1/ M2 = E1/E2 ,
    • Where E = equivalent weight
• Freundlich Adsorption Isotherm:
  •  [x/m]-Kp (1/n); n>=1
• General Electronic Configuration:
  • ns1-2

Check NIT Trichy: B.Tech (Chemical Engineering) Cut Off

Important Formulas for JEE Main 2021 Mathematics

If you concentrate well in your board examinations, your Mathematics syllabus will be done very easily. Formulas play a very important role in the preparation of mathematics section. Let us look at some important formulas list for JEE Main Maths given below-

The general form of Complex numbers x + i where ‘x’ is Real part and ‘i’ is an Imaginary part.

• Sum of nth root of unity is zero
• Product of nth root of unity (–1)n–1
• Cube roots of unity are 1, ω, ω2
  • |z1+z2|<=|z1|+|z2|; |z1+z2|>=|z1|-|z2|; |z1-z2|>=|z1|-|z2|
• If three complex numbers z1, z2, z3 are collinear then,
  • [z1 z1 1
  • z2 z2 1
  • z3 z3 1] = 0

• If ΣCosα = ΣSinα = 0, ΣCos2α = ΣSin2α = 0,
• ΣCos2nα = ΣSin2nα = 0,
• ΣCos2α = ΣSin2α = 3/2
• ΣCos3α = 3Cos(α + β + γ),
• ΣSin3α = 3Sin(α + β + γ)
• ΣCos(2α – β – γ) = 3,
• ΣSin(2α – β – γ) = 0,
• a^3 + b^3 + c^3 – 3abc = (a + b + c) (a + bω + cω^2) (a + bω^2 + cω)

Standard form of Quadratic equation

• • ax^2 + bx + c = 0
  • Sum of roots = -b/a,
  • Product of roots discriminate = b^2 – 4ac
  • If α, β are roots then Quadratic equation is x^2 – x(α + β) + αβ = 0
• Number of terms in the expansion: (x+a)n is n+1
  • Any three non coplanar vectors are linearly independent
• A system of vectors ā1, ā2,….ān are said to be linearly dependent,
  • If there, x1ā1+x2ā2+….+xnan=0
  • At least one of xi ≠0, i=1, 2, 3….n
  • And determinant = 0
• a,b,c are coplanar then [abc]=0
• If i,j,k are unit vectors then [i j k] = 1
• If a,b,c are vectors then [a+b, b+c, c+a] = 2[abc]
• (1 + x)n – 1 is divisible by x and (1 + x)n – nx –1 is divisible by x2
• If nCr-1, nCr, nCr+1 are in A.P, then (n–2r)2 = n + 2

Must Read | IIT Delhi: BTech (Mathematics and Computing), Cut Off, Fees

Integration Important Formulas for JEE Main

1. ∫xn dx = \frac{x^{n+1}}{n+1}+cn+1xn+1​+c , n ≠ -1
2. \int \frac{1}{x}\: dx = \log_{e}\left | x \right |+c∫x1​dx=loge​∣x∣+c
3. ∫e^x dx = e^x+c
4. ∫a^x dx = \frac{a^{x}}{\log_{e}a}+cloge​aax​+c
5. ∫ sin x dx  = -cos x + c
6. ∫ cos x dx  = sin x + c
7. ∫ sec² x dx  = tan x + c
8. ∫ cosec² x dx  = -cot x + c
9. ∫ sec x tan x dx = sec x + c
10. ∫ cosec x cot x dx = – cosec x + c
11. ∫ cot x dx = $\log \left|\sin x\right|+c$
12. ∫ tan x dx = $-\log \left|cosx\right|+c$
13. ∫ sec x dx = log $\left|secx+tanx\right|+c$
14. ∫ cosec x dx = log $\left|cosecx–\cot x\right|+c$
15. \int \frac{1}{\sqrt{a^{2}-x^{2}}} \; dx = \sin ^{-1}(\frac{x}{a})+c∫a2−x2​1​dx=sin−1(ax​)+c
16. \int -\frac{1}{\sqrt{a^{2}-x^{2}}} \; dx = \cos ^{-1}(\frac{x}{a})+c∫−a2−x2​1​dx=cos−1(ax​)+c
17. \int \frac{1}{{a^{2}+x^{2}}} \; dx = \frac{1}{a}\tan ^{-1}(\frac{x}{a})+c∫a2+x21​dx=a1​tan−1(ax​)+c
18. \int -\frac{1}{{a^{2}+x^{2}}} \; dx = \frac{1}{a}\cot ^{-1}(\frac{x}{a})+c∫−a2+x21​dx=a1​cot−1(ax​)+c
19. \int \frac{1}{x\sqrt{x^{2}-a^{2}}}\; dx = \frac{1}{a}\sec ^{-1}(\frac{x}{a})+c∫xx2−a2​1​dx=a1​sec−1(ax​)+c
20. \int -\frac{1}{x\sqrt{x^{2}-a^{2}}}\; dx = \frac{1}{a}\: cosec ^{-1}\left ( \frac{x}{a} \right )+c∫−xx2−a2​1​dx=a1​cosec−1(ax​)+c

What else to refer for JEE Main Important Formulas?

In order to find more in-depth important formulas for JEE Main, students can always refer to handbooks. Handbooks/Formula books are short formula books for all the major topics of each section. Coaching institutes like Allen, Aakash and Resonance provide their handbooks for all the important formulas for JEE Main. These handbooks also have JEE Main tips and tricks for some type of questions which regularly appear in JEE Main.

Free JEE Main Important Formula Handbook PDFs by Resonance

Resonance provides some free to use study material to registered users of their website. Students can download PDFs of various sample papers and study material for JEE Main. Given below are some free formula handbook PDFs for download by Resonance.

Physics Formula Handbook	Download PDF
Chemistry Formula Handbook	Download PDF
Maths Formula Handbook	Download PDF

Every year a large number of candidates fill JEE Main Application Form. This leads to cut-throat competition. To crack JEE Main 2021 with high score candidates are advised to keep a handy note of these important formulas. Here we have provided JEE Main important formulas which can be helpful for the preparation of all 3 subjects of the exam – Physics, Chemistry, and Mathematics.

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