Torsional springs, energy absorbed

The energy absorbed by a torsional spring deflected through angle 6 equals ... 

Torsional beam spring design absorbs the load energy by its twisting action through an angle zero. Fig. 4.32 is an example of its behavior is that of a shaft in torsion so that it is considered to have failed when the strength of the material in shear is exceeded. 

A torsional beam spring absorbs energy by twisting through an angle 0 (Fig. 3-14) and may thus be treated as a shaft in torsion. 

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