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WORKSHOP SCIENCE - CITS
The equations defined how force depends on mass, length and time. We use the symbols MLT (not in italics) to
indicate the fundamental dimensions of mass, length and time.
The dimensional formula of a derived quantity is an equation that shows the powers to which the fundamental
units must be raised to acquire one unit of that physical quantity. If Q is the unit of a derived quantity, MaLbTc is
the dimensional formula, and the exponents a, b, and c are the dimensions.
Some examples are Force, Velocity, Density, Heat, Power, Energy, Momentum, and Acceleration. The units used
to measure these derived quantities are referred to as derived units.
List of physical quantities
Derived quantity Symbol Description
Angular velocity ω The angle incremented in a plane by a segment
connecting an object and a reference point per unit time
Area A Extent of a surface
Area density ρA Mass per unit area
Capacitance C Stored charge per unit electric potential
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CITS : WCS - Mechanical - Exercise 1
