Advertisements
Advertisements
Question
A mild steel wire of length 2L and cross-sectional area A is stretched, well within elastic limit, horizontally between two pillars (Figure). A mass m is suspended from the mid point of the wire. Strain in the wire is ______.

Options
`x^2/(2L^2)`
`x/L`
`x^2/L`
`x^2/(2L)`
Advertisements
Solution
A mild steel wire of length 2L and cross-sectional area A is stretched, well within elastic limit, horizontally between two pillars (Figure). A mass m is suspended from the mid point of the wire. Strain in the wire is `underline(x^2/(2L^2))`.
Explanation:
Consider the diagram below

Hence, change in length
ΔL = BO + OC – (BD + DC)
= 2BO – 2BD .......(∵ BO = OC, BD = DC)
= 2(BO – BD)
= `2[(x^2 + L^2)^(1/2) - L]`
= `2L[(1 + x^2/L^2)^(1/2) - 1]`
= `2L[1 + 1/2 x^2/L^2 - 1]`
= `x^2/L` ........[∵ x << L]
Strain = `(ΔL)/(2L)`
= `(x^2/L)/(2L)`
= `x^2/(2L^2)`
APPEARS IN
RELATED QUESTIONS
A steel cable with a radius of 1.5 cm supports a chairlift at a ski area. If the maximum stress is not to exceed 108 N m–2, what is the maximum load the cable can support?
A mild steel wire of length 1.0 m and cross-sectional area 0.50 × 10–2 cm2 is stretched, well within its elastic limit, horizontally between two pillars. A mass of 100 g is suspended from the mid-point of the wire. Calculate the depression at the midpoint.
Two strips of metal are riveted together at their ends by four rivets, each of diameter 6.0 mm. What is the maximum tension that can be exerted by the riveted strip if the shearing stress on the rivet is not to exceed 6.9 × 107 Pa? Assume that each rivet is to carry one-quarter of the load.
A rope 1 cm in diameter breaks if the tension in it exceeds 500 N. The maximum tension that may be given to a similar rope of diameter 2 cm is
A heave uniform rod is hanging vertically form a fixed support. It is stretched by its won weight. The diameter of the rod is
When a metal wire is stretched by a load, the fractional change in its volume ∆V/V is proportional to
A load of 10 kg is suspended by a metal wire 3 m long and having a cross-sectional area 4 mm2. Find (a) the stress (b) the strain and (c) the elongation. Young modulus of the metal is 2.0 × 1011 N m−2.
Answer in one sentence.
How should be a force applied on a body to produce shearing stress?
Modulus of rigidity of ideal liquids is ______.
The maximum load a wire can withstand without breaking, when its length is reduced to half of its original length, will ______.
Consider two cylindrical rods of identical dimensions, one of rubber and the other of steel. Both the rods are fixed rigidly at one end to the roof. A mass M is attached to each of the free ends at the centre of the rods.
Is stress a vector quantity?
Consider a long steel bar under a tensile stress due to forces F acting at the edges along the length of the bar (Figure). Consider a plane making an angle θ with the length. What are the tensile and shearing stresses on this plane

- For what angle is the tensile stress a maximum?
- For what angle is the shearing stress a maximum?
A steel wire having a radius of 2.0 mm, carrying a load of 4 kg, is hanging from a ceiling. Given that g = 3.1πms-2, what will be the tensile stress that would be developed in the wire?
The area of the cross-section of the rope used to lift a load by a crane is 2.5 × 10-4m2. The maximum lifting capacity of the crane is 10 metric tons. To increase the lifting capacity of the crane to 25 metric tons, the required area of cross-section of the rope should be ______.
(take g = 10 ms-2)
The stress-strain graph of a material is shown in the figure. The region in which the material is elastic is ______.
The SI unit of stress is ______.
What are the dimensions of stress?
When an elastic body is in equilibrium in its altered shape, the magnitude of the external deforming force is ______.
