phy
posted by kate .
(Q1)A wire of cross sectional area of 0.00006m2 and length 50cm stretches by 0.2mm under a load of 3000n.Calculate the Young's modulus for the wire (a)80000000000Nm2(b)125000000000Nm2(c)25000000000Nm2(d)5000000000Nm2 (Q2)a square plate of side 10cm is made of a metal of linear expansivity0.00002/k.As the plate is heated from 30c to 100c.The area of one face of the plate will increase to (a)1056cm2(b)104.2cm2(c)102.8cm2(d)101.4cm2

Q1
σ=Eε
F/A = E ΔL/L
E= F•L/A• ΔL= 3000•0.5/0.00006•0.2•10⁻³ = 125000000000 N/m²
Q2
α= ΔL/L•ΔT
ΔL= α•L•ΔT=
=0.00002 •0.1•70 =0.00014 m
L₁=0.1+0.00014=0.10014 m
S₁=(0.10014)²=0.010028 m²=100.28 cm²
Respond to this Question
Similar Questions

physics
a metal wire 1.0 mm in diameter and 2.0 m long hangs vertically with a 5.0 kg mass suspended from it. if the wire stretches 1.2 mm under the tension, what is the value of the young's modulus for metal? 
physics
a wire whose crosssectional area is 4mm^2 is stretched by 0.1 mm by a certain load.if a similar wire double the area of crosssection is under the same load,then then elongation would be ans: 1)0.05mm 
mechanics of materials
Select the correct answer.The change in length of a steel wire under an applied load can be halved by keeping all other conditions constant but using: A. A different material having a Young's modulus half that of steel B half the cross … 
mechanics of materials
The change in length of a steel wire under an applied load can be halved by keeping all other conditions constant but using:which of the following is correct A. a different material having a Young's modulus half that of steel B half … 
mechanics
The change in length of a steel wire under an applied load can be halved by keeping all other conditions constant but using: A. a different material having a Young's modulus half that of steel B half the cross sectional area of the … 
Physics
The drawing shows two crates that are connected by a steel (Young's modulus 2.0 x 1011 N/m2) wire that passes over a pulley. The unstretched length of the wire is 1.8 m, and its crosssectional area is 1.4 x 105 m2. The pulley is … 
Physics
A 215kg load is hung on a wire of length of 3.50 m, crosssectional area 2.000x10^5 m2, and Young's modulus 8.00x 10^10 N/m2. What is its increase in length? 
physics
A 4.0mlong steel wire has a crosssectional area of 0.050cm2. Its proportional limit has a value of 0.0016 times its Young's modulus. Its breaking stress has a value of 0.0065 times its Young's modulus. The wire is fastened at its … 
sciencecollege physics
2. A certain wire of length L, crosssectional area A is extended by an amount ‘e’ by a force F. Given that the young’s modulus of the material of the wire is E, Show that the; a. Energy stored in the wire is given by the expression … 
Physics
A wire with cross sectional area 1.00 cm2 stretches 0.500% of its length when it is stretched with a tension of 20.0 N. What is the Young's modulus of this wire?