Modulus of Elasticity (Young's Modulus, E) - Dimensional formula: E=
Stress
Strain
- Stress = Force ∕ Area =
MLT−2
L2
=ML−1T−2 - Strain is dimensionless. - So, dimensional formula of E : [E]=ML−1T−2 Torque ( τ ) - Torque = Force × Distance - τ=(MLT−2)×L=ML2T−2 - So, dimensional formula of τ : [τ]=ML2T−2
E
τ
=
ML−1T−2
ML2T−2
Canceling M and T−2 : Thus, the dimensional formula of the required quantity is: =L−1−2=L−3 [M0L−3T0] Compare with MaLbTc a=0,b=−3,c=0
