Got you, Ashutosh 👍 — here are SSC ke liye super-short shortcut notes for Units & Dimensions (revision-friendly):
🔹 1. Basic Concept
Physical Quantity = Numerical value + Unit
Example: 5 m, 10 kg
🔹 2. Fundamental (Base) Quantities (Yaad trick: MLT KAT)
QuantityUnitSymbolLengthmetermMasskilogramkgTimesecondsTemperaturekelvinKCurrentampereA
🔹 3. Derived Quantities (Most Important for SSC)
Velocity = m/s → [LT⁻¹]
Acceleration = m/s² → [LT⁻²]
Force = kg·m/s² → [MLT⁻²]
Work/Energy = Force × distance → [ML²T⁻²]
Power = Work/time → [ML²T⁻³]
Pressure = Force/Area → [ML⁻¹T⁻²]
Density = Mass/Volume → [ML⁻³]
👉 Shortcut yaad trick:
Force → MLT⁻²
Energy → Force × L → ML²T⁻²
Power → Energy / T → ML²T⁻³
🔹 4. Important Dimensionless Quantities (SSC favourite)
(No unit, no dimension)
Strain
Refractive Index
Relative Density
Angle
🔹 5. Use of Dimensional Formula
Formula check karna
Unit convert karna
Relation find karna
🔹 6. Important Unit Conversions (Rapid Fire)
1 km = 1000 m
1 hour = 3600 s
1 N = 1 kg·m/s²
1 J = 1 N·m
1 W = 1 J/s
🔹 7. Exam Hacks (Very Important ⚡)
Dimensions me constant ignore karo
Addition/subtraction me same dimension hona chahiye
Trigonometric, log → dimensionless input
🔹 8. Most Repeated Question Pattern
“Find dimension of X”
“Which is dimensionally correct?”
“Find relation between quantities”
🔹 Ultra Shortcut Revision (30 sec me)
Force → MLT⁻²
Energy → ML²T⁻²
Power → ML²T⁻³
Pressure → ML⁻¹T⁻²
Density → ML⁻³
🔹 1. Basic Concept
Physical Quantity = Numerical value + Unit
Example: 5 m, 10 kg
🔹 2. Fundamental (Base) Quantities (Yaad trick: MLT KAT)
QuantityUnitSymbolLengthmetermMasskilogramkgTimesecondsTemperaturekelvinKCurrentampereA
🔹 3. Derived Quantities (Most Important for SSC)
Velocity = m/s → [LT⁻¹]
Acceleration = m/s² → [LT⁻²]
Force = kg·m/s² → [MLT⁻²]
Work/Energy = Force × distance → [ML²T⁻²]
Power = Work/time → [ML²T⁻³]
Pressure = Force/Area → [ML⁻¹T⁻²]
Density = Mass/Volume → [ML⁻³]
👉 Shortcut yaad trick:
Force → MLT⁻²
Energy → Force × L → ML²T⁻²
Power → Energy / T → ML²T⁻³
🔹 4. Important Dimensionless Quantities (SSC favourite)
(No unit, no dimension)
Strain
Refractive Index
Relative Density
Angle
🔹 5. Use of Dimensional Formula
Formula check karna
Unit convert karna
Relation find karna
🔹 6. Important Unit Conversions (Rapid Fire)
1 km = 1000 m
1 hour = 3600 s
1 N = 1 kg·m/s²
1 J = 1 N·m
1 W = 1 J/s
🔹 7. Exam Hacks (Very Important ⚡)
Dimensions me constant ignore karo
Addition/subtraction me same dimension hona chahiye
Trigonometric, log → dimensionless input
🔹 8. Most Repeated Question Pattern
“Find dimension of X”
“Which is dimensionally correct?”
“Find relation between quantities”
🔹 Ultra Shortcut Revision (30 sec me)
Force → MLT⁻²
Energy → ML²T⁻²
Power → ML²T⁻³
Pressure → ML⁻¹T⁻²
Density → ML⁻³
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