A material has modulus of rigidity equal to 0.4x10^5 N/mm2 and Bulk modulus
equal to 0.95 x10^5N/mm2 The Young's modulus value in GPa is..
Answers
Given info : A material has modulus of rigidity equal to 0.4 x 10^5 N/mm² and Bulk modulus
equal to 0.95 x 10^5 N/mm².
To find : The Young's modulus value in GPa is..
solution : we know,
E = 2G(1 + μ). ...(1)
E = 3K(1 - 2μ). ...(2)
from equations (1) and (2),
(E/2G - 1) = (1 - E/3K)/2
⇒(E - 2G)/2G = (3K - E)/6K
using G = modulus of rigidity = 0.4 × 10^5 N/mm²
K = bulk modulus = 0.95 × 10^5 N/mm²
⇒(E - 2 × 0.4 × 10^5)/2 × 0.4 × 10^5 = (3 × 0.95 × 10^5 - E)/6 × 0.95 × 10^5
⇒(E - 0.8 × 10^5) × 5.7 × 10^5 = 0.8 × 10^5(2.85 × 10^5 - E)
⇒(E - 0.8 × 10^5) × 0.7 = (2.85 × 10^5 - E)
⇒0.7E - 0.56 × 10^5 = 2.85 × 10^5 - E
⇒1.7E = 3.41 × 10^5
⇒E ≈ 2 × 10^5 N/mm² = 2 × 10¹¹ N/m²
= 200 GPa
Therefore the Young's modulus value in GPa is 200 (approx).
Answer:
Step-by-step explanation: