UNITS AND DIMENSIONS
1. Fundamental & Supplementary Quantities
7 Fundamental SI Base Quantities Supplementary Quantities
QUANTITY SI UNIT DIM. Plane Angle (θ): θ = Arc / Radius
SI Unit: Radian (rad)
Mass Kilogram (kg) [M]
Dimension: Dimensionless [M0L0T0]
Length Meter (m) [L]
Time Second (s) [T] Solid Angle (Ω): Ω = Area / Radius2
SI Unit: Steradian (sr)
Electric Current Ampere (A) [A]
Dimension: Dimensionless [M0L0T0]
Temperature Kelvin (K) [K]
Amount of Substance Mole (mol) [mol]
Luminous Intensity Candela (cd) [cd]
2. Most Frequently Tested Dimensional Formulas in NEET
PHYSICAL QUANTITY DEFINING FORMULA DIMENSIONAL FORMULA SI UNIT
Force / Weight F=m·a [M1 L1 T-2] Newton (N)
Work / Energy / Torque W=F·d [M1 L2 T-2] Joule (J)
Pressure / Stress / Young's Modulus P=F/A [M1 L-1 T-2] Pascal (Pa)
Momentum / Impulse p = m · v / I = F · Δt [M1 L1 T-1] kg·m/s / N·s
Universal Gravitational Constant (G) G = F · r2 / (m1m2) [M-1 L3 T-2] N·m2/kg2
Planck's Constant (h) h=E/ν [M1 L2 T-1] J·s
Coefficient of Viscosity (η) η = F / [A(dv/dx)] [M1 L-1 T-1] Pa·s
Surface Tension (T) T=F/L [M1 L0 T-2] N/m
Permittivity of Free Space (ε0) ε0 = q1q2 / (4πF r2) [M-1 L-3 T4 A2] F/m
Permeability of Free Space (μ0) μ0 = 2πFr / (I1I2L) [M1 L1 T-2 A-2] H/m
Electric Resistance (R) R=V/I [M1 L2 T-3 A-2] Ohm (Ω)
Capacitance (C) C=Q/V [M-1 L-2 T4 A2] Farad (F)
NEET Exam Tip: Speed Trick
Direct relations such as 1 / √(μ0ε0) = c (Speed of Light) and E = hν are frequently asked to instantly check
dimensions without deriving from basic principles.
NEET Physics Revision Series Page 1 of 2
1. Fundamental & Supplementary Quantities
7 Fundamental SI Base Quantities Supplementary Quantities
QUANTITY SI UNIT DIM. Plane Angle (θ): θ = Arc / Radius
SI Unit: Radian (rad)
Mass Kilogram (kg) [M]
Dimension: Dimensionless [M0L0T0]
Length Meter (m) [L]
Time Second (s) [T] Solid Angle (Ω): Ω = Area / Radius2
SI Unit: Steradian (sr)
Electric Current Ampere (A) [A]
Dimension: Dimensionless [M0L0T0]
Temperature Kelvin (K) [K]
Amount of Substance Mole (mol) [mol]
Luminous Intensity Candela (cd) [cd]
2. Most Frequently Tested Dimensional Formulas in NEET
PHYSICAL QUANTITY DEFINING FORMULA DIMENSIONAL FORMULA SI UNIT
Force / Weight F=m·a [M1 L1 T-2] Newton (N)
Work / Energy / Torque W=F·d [M1 L2 T-2] Joule (J)
Pressure / Stress / Young's Modulus P=F/A [M1 L-1 T-2] Pascal (Pa)
Momentum / Impulse p = m · v / I = F · Δt [M1 L1 T-1] kg·m/s / N·s
Universal Gravitational Constant (G) G = F · r2 / (m1m2) [M-1 L3 T-2] N·m2/kg2
Planck's Constant (h) h=E/ν [M1 L2 T-1] J·s
Coefficient of Viscosity (η) η = F / [A(dv/dx)] [M1 L-1 T-1] Pa·s
Surface Tension (T) T=F/L [M1 L0 T-2] N/m
Permittivity of Free Space (ε0) ε0 = q1q2 / (4πF r2) [M-1 L-3 T4 A2] F/m
Permeability of Free Space (μ0) μ0 = 2πFr / (I1I2L) [M1 L1 T-2 A-2] H/m
Electric Resistance (R) R=V/I [M1 L2 T-3 A-2] Ohm (Ω)
Capacitance (C) C=Q/V [M-1 L-2 T4 A2] Farad (F)
NEET Exam Tip: Speed Trick
Direct relations such as 1 / √(μ0ε0) = c (Speed of Light) and E = hν are frequently asked to instantly check
dimensions without deriving from basic principles.
NEET Physics Revision Series Page 1 of 2
