Question

What is Young's Modulus and what is it's si unit and dimensional formula///?

Answer 1

Refractive index = speed of light in air/ speed of light in medium

Hence refractive index is dimension less quantity.

Young's Modulus = normal stress/longitudinal strain

S.I unit  = Nm​-2

Dimension = [M1L-1T-2]

Answer 2

$\huge\mathfrak\red{Answer :}$


$\huge\textbf{Young's Modulus (Y) :}$

It is defined as ratio of normal stress with longitudinal strain.

i.e.

Y = $\dfrac{Normal\:Strain}{Longitudinal\:stress}$

Y = $\dfrac{\frac{F}{A}}{\frac{\delta\:L}{L}}$

Y = $\dfrac{FL}{A\:\delta\:L}$

→ S.I. unit = N/m²

→ Dimension = [M¹L-¹T-²]

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