A) \[2\times 1{{0}^{7}}N\]
B) \[1\times 1{{0}^{5}}N\]
C) \[2\times 1{{0}^{9}}N\]
D) \[3\times 1{{0}^{-5}}N\]
Correct Answer: B
Solution :
[b] Young's modulus \[=\frac{Thermal\text{ }stress}{Stain}=\frac{F/A}{\Delta L/L}\] \[Y=\frac{F}{A.\alpha .\Delta \theta }\left( \because \frac{\Delta L}{L}\alpha \,\Delta \theta \right)\] Force developed in the rail \[F=Y\,\alpha \,\Delta t\] \[=2\times l{{0}^{11}}\times 40\times l{{0}^{-4}}\times l.2\times 1{{0}^{-5}}\times 10\] \[=9.6\times {{10}^{4}}=1\,\times l{{0}^{5}}N\]You need to login to perform this action.
You will be redirected in
3 sec