Young's modulus of elasticity for "A" and "B" are "Y"_"A" = 1.1×10^11\ "Pa" and "Y"_"B" = 2.0 xx 10^11\ "Pa". Which is more elastic and why?

1 Answer
Mar 18, 2018

substance B

Explanation:

Young's modulus = (Stress)/(strai n)

Now,elasticity means the relative hindrance by an object during causing distortion of its structure i.e strain.

Now,stress means force applied per unit area i.e a measurement of pressure.

So,we can conclude that to cause a certain amount of strain of a more elastic substance we need to apply larger amount of stress.

Suppose,a material has Young's modulus Y and the other have Y',for causing same amount of strain x we need to apply stress s for the first one and s' for the second one,where s>s'

so,for the first substance we can write,

Y=s/x or, x=s/Y

and for the second substance,

Y'=(s')/x

or, x=(s')/(Y')

so,s/Y =(s')/(Y')

or, s/(s') =Y/(Y')

As,s>s' so Y>Y'

That means a substance which is more elastic will have higher value of Young's modulus.