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Quantity       SI Unit                     Definition

Weight                     N       Force on an object due to gravity

Period                     s       Time needed to complete one oscillation

Density                  kg/m3     Mass per unit volume

Speed                     m/s      Distance travelled per unit time

Acceleration              m/s2     Change in velocity per unit time

Force                      N       Rate of change in momentum

Moment of Force           Nm       Turning effect of a force about a point and is
                                   calculated by multiplying the force and the
                                   perpendicular distance from the pivot.

Work Done                  J       Amount of energy converted by a force
                                   acting through a distance

Power                      W       Rate of Work Done

Pressure                Pa, N/m2   Amount of force exerted normally on an
                                   object per unit area

Specific Heat Capacity   J/(kg K)   Amount of heat required to raise unit mass
                                   of a substance by unit temperature

Specific Latent Heat       J/kg     Amount of heat required to change the state
                                   of a unit mass of the object without any
                                   change in temperature

Frequency                 Hz       Number of cycles completed per unit time

Wavelength                 m       Distance between two successive points on
                                   waves that are in phase

Potential Difference       V       Amount of energy converted to other forms
                                   of energy when one coulomb of positive
                                   charge passes between the points.

E.M.F                      V       Work done by the source in driving a unit
                                   charge round a complete circuit.

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Physics Units & Definitions

  • 1. Quantity SI Unit Definition Weight N Force on an object due to gravity Period s Time needed to complete one oscillation Density kg/m3 Mass per unit volume Speed m/s Distance travelled per unit time Acceleration m/s2 Change in velocity per unit time Force N Rate of change in momentum Moment of Force Nm Turning effect of a force about a point and is calculated by multiplying the force and the perpendicular distance from the pivot. Work Done J Amount of energy converted by a force acting through a distance Power W Rate of Work Done Pressure Pa, N/m2 Amount of force exerted normally on an object per unit area Specific Heat Capacity J/(kg K) Amount of heat required to raise unit mass of a substance by unit temperature Specific Latent Heat J/kg Amount of heat required to change the state of a unit mass of the object without any change in temperature Frequency Hz Number of cycles completed per unit time Wavelength m Distance between two successive points on waves that are in phase Potential Difference V Amount of energy converted to other forms of energy when one coulomb of positive charge passes between the points. E.M.F V Work done by the source in driving a unit charge round a complete circuit.