Pressure $=f / A$

So, $[$ stress $]=[$ Pressuue $]=\left[M L^{-1} T^{-2}\right]$

Hiso, $Y=\frac{\text { stress }}{\text { strain }}$ (strain is dimensionliss)

$\therefore Y=f / A=\left[M L^{-1} T^{-2}\right]$

$\therefore$ All the there has seme dimenion equals $\left[ HL ^{-1} T^{-2}\right]$