Quantity

A thing that can be measured and shows the result in number

 

A. Basic Quantity

The basic quantity is independent physical quantities that are not possible to be expressed in terms of any other physical quantity. These quantities are used to derive all other physical quantities.

 

NoBasic QuantitySI unitUnit Symbol1Lengthmeterm2Masskilogramkg3Timeseconds4Electric currentampereA5TemperaturekelvinK6Amount of substancemolemol7Luminous intensitycandelacd

B. Derived Quantity

A quantity that is derived from a basic quantity

 

NoDerivative QuantitySymbolPhysical FormulaSI UnitDerived From1AreaALength×Breadthm2length2VolumeVLength×Breadth×Heightm3length3SpeedvDistanceTimems1length and time4VelocityvDisplacementTimem.s1length and time5AccelerationaVelocityTimem.s2length and time6DensityρMassVolumekg.m3mass and length7FrequencyfNumber of WavesTimes1 or Hztime8ForceFMass×Accelerationkg.m.s2mass, length & time9WorkWForce×Displacementkg.m2.s2mass, length & time10PowerPWorkTimekg.m2.s3mass, length & time11Electric ChargeQElectric Current×TimeA.s or Celectric current & time12Electric Potential DifferenceVPotential EnergyChargekg.m2.s3.A1mass, length, time & electric current13PressurePForceAreakg.m1.s2 or Pamass, length & time14Electrical CapacitanceCCharge StoredPotential differences4.A2.m2.kg1 or Faradtime, electric current, length & mass15ImpulseIForce×TimeKg.m2.s1 or N.smass, length & time16MomentumpMass×VelocityKg.m2.s1 or N.smass, length & time17TorqueτForce×DistanceKg.m2.s2 or N.mmass, length & time

C. Quantity Based On Its Direction

 

Scalar QuantityVector QuantityA quantity that is stated by numbersA quantity that is stated by numbers and directionExample: length, mass, time, temperature, Area, speedExample: displacement, velocity, acceleration, forcedensity, pressure, work, energy, power, chargeweight, impulse, momentum, torque

Exercise

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