2022 Mechanical Properties of SolidsElastic Moduli – Shear Modulus Medium Question 6 of 15 in Mechanical Properties of Solids

The stretching of a spring is determined by the shear modulus of the material of the spring

Reason: A coil spring of copper has more tensile strength than a steel spring of same dimensions.
A Both A and R are true and R is the correct explanation of A
B Both A and R are true but R is NOT the correct explanation of A
C A is true but R is false
D A is false but R is true

The answer is C.

Solution

In the stretching of a coil spring, the shape of the wire changes (it is twisted), so the shear modulus of the material is used – Assertion is true. Young's modulus (and tensile strength) of copper is less than that of steel, $Y_{copper} < Y_{steel}$, so a copper spring does not have more tensile strength than a steel spring – Reason is false. So A is true but R is false.

Concept shear modulus and spring stretching

Mechanical Properties of Solids in past papers

15 questions from this chapter have appeared across 11 exam years.