Force Exerted by Contracting or Stretching a Material

Any strain exerted on a material causes an internal elastic stress.  The force applied on a material when contracting or stretching is related to how much the length of the object changes.

 

Force Exerted by Contracting or Stretching a Material formula
\(\large{ F =    \frac { \lambda \;A\; l_c  } { l_o  }  }\)
Symbol	English	Metric
\(\large{ F }\) = force exerted	\(\large{lbf}\)	\(\large{N}\)
\(\large{ l_c }\) = change in length	\(\large{ft}\)	\(\large{m}\)
\(\large{ l_o }\) = origional length	\(\large{ft}\)	\(\large{m}\)
\(\large{ \lambda }\)  (Greek symbol lambda) = modulus of elasticity	\(\large{\frac{lbf}{in^2}}\)	\(\large{Pa}\)
\(\large{ A }\) = origional area cross-section through which the force is applied	\(\large{ft^2}\)	\(\large{m^2}\)