Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main201910 Apr 2019Evening ShiftPhysicsMechanical Properties of SolidsActual

In an experiment, brass and steel wires of length 1 m each with areas of cross section 1 m m 2 are used. The wires are connected in series and one end of the combined wire is connected to a rigid support and other end is subjected to elongation. The stress required to produce a net elongation of 0.2 m m is, [Given, the Young's Modulus for steel and brass are, respectively, 120 × 10 9 N / m 2 and 60 × 10

Options

  1. A8.0 × 10 6 N / m 2
  2. B1.2 × 10 6 N / m 2
  3. C0.2 × 10 6 N / m 2
  4. D1.8 × 10 6 N / m 2

Correct answer

A. 8.0 × 10 6 N / m 2

Step-by-step solution

Stress will be same in both rods Stress = Y 1 Δ l 1 l = Y 2 Δ l 2 l … (1) And Δ l 1 + Δ l 2 = 0.2 × 10 - 3   m … (2) From equation (1) and (2) Stress × l Y 1 + l Y 2 = 0 .2 × 10 - 3   m Stress × 1 120 × 10 9 + 1 60 × 10 9 = 0.2 × 10 - 3   m Stress = 8 × 10 6   N / m 2

Practice Mechanical Properties of Solids on Quantrex Academy →

More from Mechanical Properties of Solids

Figure represents the extension ( l ) of a wire of length 1 meter, suspended from the ceiling of the room at one end with a load W connected to the other end. If the cross-sectiona 2026A lift of mass 1600 kg is supported by thick iron wire. If the maximum stress which the wire can withstand is 4 10^8 N/m ^2 and its radius is 4 mm, then maximum acceleration the li 2026The two wires A and B of equal cross-section but of different materials are joined together. The ratio of Young's modulus of wire A and wire B is 20/11 . When the joined wire is ke 2026A copper wire of length 3 m is stretched by 3 mm by applying an external force. The volume of the wire is 600 10⁻⁶ m ^3 . The elastic potential energy stored in the wire in stretch 2026The Young's modulus of steel wire of radius r and length L is Y . If the radius r and length L of the wire are doubled then the value of Y 2026Two wires as shown in the figure below, made of steel and have breaking stress of 12 10^8 N/m ^2 . Area of cross-section of upper wire is 0.008 cm ^2 and of lower wire is 0.004 cm 2026A cube has side length 5 cm and modulus of rigidity 10^5 N/m ^2 . The displacement produced by a force of 10 N in the upper face of cube is _____ mm. 2026A metal string A is suspended from a rigid support and its free end is attached to a block of mass M . Second block having mass 2M is suspended at the bottom of the first block usi 2026 Full Mechanical Properties of Solids list All JEE Main PYQs