Student Login

Home›Chapters›Mechanical Properties of Solids PYQs›Wire Combinations & Special Cases›Question 18

JEE Main 2021 (25 Jul, Shift 1) · Wire Combinations & Special Cases

Wire Combinations & Special Cases question from JEE Main 2021 (25 Jul, Shift 1)

Q18JEE Main 2021 · 25 JUL · SHIFT 1Medium

Wire Combinations & Special Cases

Two wires of same length and radius are joined end to end and loaded. The Young's moduli of the materials of the two wires are Y1 and Y2. The combination behaves as a single wire then its Young's modulus is:

Show answer and solution

Answer: (b)

Same load $F$ , area $A$ , each of length $L$ : $\Delta l = \frac{FL}{AY_1} + \frac{FL}{AY_2}$
As a single wire of length $2L$ : $\Delta l = \frac{F(2L)}{AY}$
$\frac{2}{Y} = \frac{1}{Y_1} + \frac{1}{Y_2} \Rightarrow Y = \frac{2Y_1Y_2}{Y_1 + Y_2}$
So the answer is (b).

Report a mistake

More questions on Wire Combinations & Special Cases

A uniform heavy rod of weight 10 kg ms−2, cross-sectional area 100 cm2 and length 20 cm…JEE Main 2021 (31 Aug, Shift 1)
The length of a metal wire is l1, when the tension in it is T1 and is l2 when the tension…JEE Main 2021 (20 Jul, Shift 2)
The value of tension in a long thin metal wire has been changed from T1 to T2. The…JEE Main 2021 (20 Jul, Shift 1)
The length of metallic wire is l1 when tension in it is T1. It is l2 when the tension is…JEE Main 2021 (26 Feb, Shift 2)
An object of mass m is suspended at the end of a massless wire of length L and area of…JEE Main 2020 (6 Sep, Shift 1)
In an experiment, brass and steel wires of length 1 m each with areas of cross section…JEE Main 2019 (10 Apr, Shift 2)
A load of mass M kg is suspended from a steel wire of length 2m and radius 1.0 mm in…JEE Main 2019 (12 Jan, Shift 2)
A uniformly tapering conical wire is made from a material of Young’s modulus Y and has a…JEE Main 2016 (9 Apr, Shift 1)