Q. 7

# Two persons pull a rope towards themselves. Each person exerts a force of 100 N on the rope. Find the Young modulus of the material of the rope if it extends in length by 1 cm. Original length of the rope = 2 m and the area of cross section = 2 cm^{2}.

Answer :

1 × 10^{8} N m^{-2}

Given, Force,

Cross-sectional area of rope,

Length of rope,

Extension is rope,

We know, stress,

And strain is given by ,

Young’s modulus then becomes,

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