Mechanical Engineering Fundamentals - Unit Conversion

Vocabulary flashcards covering unit conversion methods, SI prefixes, derived unit definitions, and dimensional rules from the mechanical engineering review material.

Equivalent Fraction Method (Unit Cancellation)

A conversion technique in which a quantity is multiplied by a fraction whose numerator and denominator represent equal physical values, giving the fraction a value of $1$ so only the unit changes without altering the quantity.

SI Prefix Tera ($T$)

An SI prefix representing a multiplying factor of $10^{12}$.

SI Prefix Giga ($G$)

An SI prefix representing a multiplying factor of $10^9$.

SI Prefix Mega ($M$)

An SI prefix representing a multiplying factor of $10^6$.

SI Prefix Kilo ($k$)

An SI prefix representing a multiplying factor of $10^3$.

SI Prefix Milli ($m$)

An SI prefix representing a multiplying factor of $10^{-3}$.

SI Prefix Micro ($\mu$)

An SI prefix representing a multiplying factor of $10^{-6}$.

SI Prefix Nano ($n$)

An SI prefix representing a multiplying factor of $10^{-9}$.

SI Prefix Pico ($p$)

An SI prefix representing a multiplying factor of $10^{-12}$.

Area Conversion Rule

A mathematical conversion rule stating that for quadratic quantities (such as $m^2$ and $cm^2$), the prefix multiplier must be squared, meaning $1\,m^2 = 100\,cm \times 100\,cm = 10\,000\,cm^2 = 10^4\,cm^2$.

Volume Conversion Rule

A mathematical conversion rule stating that for cubic quantities (such as $m^3$ and $mm^3$), the prefix multiplier must be cubed, meaning $1\,m^3 = 1000^3\,mm^3 = 10^9\,mm^3$, and $1\,mm^3 = 10^{-9}\,m^3$.

Newton ($N$)

A derived unit defined as an exact identity where $1\,N = 1\,kg \cdot m/s^2$, which functions as a renaming rather than requiring a numerical conversion factor.

Joule ($J$)

A derived unit defined as an exact identity where $1\,J = 1\,N \cdot m$, requiring unit renaming rather than a numerical conversion factor.

Watt ($W$)

A derived unit defined as an exact identity where $1\,W = 1\,J/s$.

Liter Identity

A volumetric definition stating that $1\,l = 1\,dm^3$.

Milliliter Identity

A volumetric definition stating that $1\,ml = 1\,cm^3$.

Chain Rule for Compound Units

A conversion procedure where the numerator and the denominator of a compound unit are converted separately in two linked steps.

Speed Conversion Rule ($km/h$ to $m/s$)

A conversion shortcut where converting from $km/h$ to $m/s$ is performed by dividing by $3.6$, and converting from $m/s$ to $km/h$ is performed by multiplying by $3.6$.

Rotational Speed Conversion ($rev/min$ to $rev/s$)

A conversion process where revolutions per minute are converted to revolutions per second by dividing by $60$.

Rotational Speed Conversion ($rev/min$ to $rev/h$)

A conversion process where revolutions per minute are converted to revolutions per hour by multiplying by $60$.

Metric Ton ($t$)

A unit of mass defined as $1\,t = 1000\,kg$.