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The basic units for all CSI Software include force (lbs, kip, N, kN, etc.),
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length
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(ft,
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in,
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m,
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mm,
...
etc.),
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time
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(second),
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and
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temperature
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(F,
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C).
...
...
is
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then
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derived
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from
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these
...
values.
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Some
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notes
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which
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concern
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force
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and
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mass
...
units
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are
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as
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follows:
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- lbs
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- and
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- kips
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- are
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- only
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- used
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- as
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- force
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- units,
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- not
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- mass
...
- units
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- Consistent
...
- mass
...
- units
...
- are
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- force
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- divided
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- by
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- unit
...
- acceleration,
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- given
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- as
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- F/(L/T
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- 2
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- ),
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- in which L
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- is
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- length
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- and
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- T
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- is
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- time.
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- Weight
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- is
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- a
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- force.
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- Given SI units, in which force is in Newtons (N),
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- the
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- consistent
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- mass
...
- unit
...
- is
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- N*sec
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- 2
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- /m
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- =
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- kg.
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- Given US Customary, in which force is in pounds (lbs),
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- the
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- consistent
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- mass
...
- unit
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- is
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- lbs*sec
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- 2
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- /ft
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- =
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- slug.
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- Under
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- a
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- unit
...
- acceleration,
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- a
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- mass
...
- of
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- one
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- slug
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- generates
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- a
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- one
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- pound
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- force.
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- When
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- accelerated
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- by
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- gravity
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- (g),
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- this
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- same
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- mass
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- generates
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- a
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- force
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- of
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- 32.2
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- lbs.
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The
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pound-mass
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unit
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is
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not
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a
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consistent
...
unit,
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where
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1
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slug
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=
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32.2
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pound-mass.
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Additional
...
information
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is
...
available
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in
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the
...
Wikipedia
...
...
...
article.
- Weight density has units of F/L3
- Consistent mass density has units of (F/(L/T
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- 2
...
- ))/L
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- 3
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- =
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- F*T
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- 2
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- /L
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- 4
- The relationship between weight and mass, and weight density and mass density, is W = M * g, all in consistent units.
- To convert weight density W = 150 lbs/ft3 into mass density (kip-in),
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- the
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- calculation
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- proceeds
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- as
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- follows:
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M = W / g = 150 lbs/ft
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- 3
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- /
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- (32.2
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- ft/sec
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- 2
...
- )
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- =
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- 4.658
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- lbs*sec
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- 2
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- /ft
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- 4
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- *
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- (kip
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- /
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- 1000
...
- lbs)
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- *
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- (ft
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- /
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- 12
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- in)
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- 4
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- =
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- 2.246E-7
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- kip*sec
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- 2
...
- /in
...
- 4