Loading [MathJax]/jax/element/mml/optable/BasicLatin.js

CBSE Questions for Class 11 Engineering Physics Mechanical Properties Of Solids Quiz 11 - MCQExams.com

If the speed of longitudinal wave equals 10 times the speed of the transverse waves in a stretched wire of material which has modulus of elasticity E, then the stress in the wire is
  • 100E
  • E100
  • E10
  • 10E
Two wires of the same material have masses in the ratio 3:The ratio of their extensions under the same load if their lengths are in the ratio 9:10 is
  • 5 : 3
  • 27 : 40
  • 6 : 5
  • 27 : 25
A 40 cm wire having a mass 3.2 gm and area of cross-section 1 mm2 is stretched between two supports 40.05 cm apart. In its fundamental note, the wire vibrates with a frequency 220 Hz. The Young's molulus is :
  • 1.98×1011 N/m2
  • 2.2×1011 N/m2
  • 3.96×1011 N/m2
  • 3.2×1011 N/m2
The extension produced in a wire by the application of a load is 3.0 mm. The extension produced in a wire of the same material and length but half the radius by the same load is:
  • 5 mm
  • 9 mm
  • 12 mm
  • 13 mm
The σ of a material is 0.If a longitudinal strain of 4.0×103 is caused, by what percentage will the volume change -
  • 0.48 %
  • 0.32 %
  • 0.24 %
  • 0.50 %
The force required to punch a square hole 2 cm side in steel sheet 2 mm thick is:-
(shearing stress of steel sheet =3.5×108N/m2)
  • 5.6×104N
  • 3.4×104N
  • 9.1×104N
  • 6.8×104N
In case of bending of a beam, depression δ depends on Young modulus of elasticity Y as
  • Y
  • Y2
  • Y1
  • Y2
When a wire is stretched, an amount of work is done. What is the amount of work done in stretching a wire through 0.1mm, if its length is 2m and area of cross - section, 106m2(Y=2×1011N/m2)
  • 5×101J
  • 5×102
  • 5×103J
  • 5×104J
On suspending a weight Mg, the length l of elastic wire and area of cross-section A its length becomes double the initial length. the instantaneous stress action on the wire is
  • Mg/A
  • Mg/2A
  • 2Mg/A
  • 4Mg/A
A bar is subjected to an axial forces as shown in figure. Find the total elongation in the bar. (E is the modulus of elasticity of the bar and A is its cross-section)
1278350_bc14dab9962442dcb3a33e9ff9e01537.png
  • FIAE
  • 2FIAE
  • 3FIAE
  • 4FIAE
When a weight of 10 kg is suspended from a copper wire of length 3 meters and diameter 0.4 mm, its length increases by 2.4 cm. If the diameter of the wire is doubled, then the extension in its length will be-
  • 9.6 cm
  • 4.8 cm
  • 1.2 cm
  • 0.6 cm
A wire is subjected to a tensile stress. If A represents area of cross-section, L represents original length, I represents extension and Y is Young's modulus of elasticity, then elastic potential energy of the stretched wire is
  • U=2LAYI2
  • U=AL2YI2
  • U=AY2LI2
  • U=14AYLI2
A square frame of ABCD consisting of five steel bars of cross section area 400mm2 and joined by pivot is subjected to action of two forces P=40kN in the direction of the diagonal as shown.Find change in angle at A if Young's modulus Y=2×105N/min.
1289747_213c2ac74d2e4712a3ca815b11769c70.png
  • 12000rad
  • 11000rad
  • 21000rad
  • 31000rad
The strain produced in the wire of length 60 cm is 1%, the change in the length of wire is
  • 0.6 cm
  • 6 cm
  • 60 cm
  • 0.016 cm
For maximum extension with given load for a wire with same value of Young's modulus of elasticity, which is true?
  • l=300cm,d=10cm
  • l=200cm,d=5cm
  • l=100cm,d=2cm
  • l=50cm,d=0.5cm

A steel bar of cross-section 500 mm and length 1 m acted upon by two forces as shown If Young modulus of elasticity of steel is 200×109 N/m2 then elongation of the rod is 


1311217_8321896861be43d798700abe2ec8819c.png
  • 0.05 mm
  • 0.5 mm
  • 0.1 mm
  • 0.2 mm
A wire of density 9×103Kg/m3 is stretched between two clamps 1 m apart and is stretched to an extension of 4.9×104 meter, Young's modulus of material is 9×1010N/m2. Then 
  • The lowest frequency of standing waveis 35 Hz
  • The frequency of 1 st overtone is 70 Hz
  • The frequency of 1 st overtone iis 105 Hz
  • A and B both
A metal wire having Poisson's ratio 14 Young's modulud 8×1010N/m2 is stretched force, which produces a lateral strain of 0.02 it. The elastic potential energy stored per volume in wire is[inJ/m3]
  • 2.56×104
  • 1.78×102
  • 3.72×102
  • 3.18×105
The bulk modulus of gas is 6×103N/m2. The additional pressure needed to reduce the volume of liquid by 10% is
  • 1200N/m2
  • 600N/m2
  • 2400N/m2
  • 1600N/m2
A wire is stretched under a force. If the wire suddenly snaps, the temperature of the wire
  • Remains the same
  • Decreases
  • Increases
  • First decreases then increases
The bulk modulus of a spherical object is B. If it is subjected to uniform pressure p, the fractional decrease in radius is
  • pB
  • B3p
  • 3pB
  • p3B
When a rubber cord is stretched, the change in volume with respect to change in its linear dimensions is negligible. The Poisson's ratio for rubber is 
  • 1
  • 0.25
  • 0.5
  • 0.75
The maximum intensity of fringes in Young's experiment is l. If one of the slits is closed , then intensity at that place becomes I0. then relation between I and I0 is
  • I=I0
  • I=2I0
  • I=4I0
  • there is no relation between I and I0
When the load on a wire is increased from 3kgwt to 8kgwt, the elongation increases from 0.61mmto 1.02mm . The required work done during the extension of the wire, is
  • 16×103J
  • 8×102J
  • 20×102J
  • 31×103J
A copper wire and a steel wire of the same diameter and length 1 m and 2 m respectively are connected end and a force is applied which stretches their combined length by 1 cm. How much each wire is elongated respectively. Y of copper = 1.2×1010 Mm2 and Y of steel +2.0×1010Nm2
  • 0.45 cm, 0.55 cm
  • 0.55 cm, 0.45 cm
  • 0.045 cm , 0.55 cm
  • 0.45 cm, 0.055 cm
 When a pressure of 100 atmosphere is applied on a spherical ball of rubber, then its volume reduces to 0.01% . The bulk modulus of the material of the rubber in dyne cm2 is
  • 10×1012
  • 100×1012
  • 1×1012
  • 20×1012
If rigidity modulus is 2.6 times of youngs modulus then the value of poission's ratio is 
  • 0.2
  • 0.3
  • 0.5
  • 0.1
A steel wire of mass 3.16 Kg is stretched to a tensile strain of 1 x103. What is the elastic deformation energy if density p=7.9g/cc and Y=2x1011N/m2
  • 4 KJ
  • 0.4 KJ
  • 0.04 KJ
  • 40 J
Find the intensity on the screen at O if only S3 is covered 
  • 3Io7
  • 3Io7
  • 3I27
  • Io2
A 2.0 m long steel cable has cross-sectional area of 0.30cm2. A 550 kg load is now hung from the cable. Assume that the cable behaves like a solid rod with an uniform cross-sectional area. Then the stress of the cable is:
  • 1.8×108Pa
  • 2.8×108Pa
  • 18×108Pa
  • 28×108Pa
Two wires of length l, radius r and length 2l, radius 2r having same Young's modulus Y are hung with weight mg. Net elongation is
  • 3 mgl/2πr2Y
  • 1 mgl/2πr2Y
  • 2 mgl/3πr2Y
  • 3 mgl/3πr2Y
The time after which the block reaches the position where is laming maximum elongation is
  • 2πmk
  • πmk
  • π2mk
  • πm2k
All three sliits are now uncovered  and a transparent plate of thickness 1.4 μ and refreactive index 1.25 is placecd  in front of S2. Rresultant intensity at point O is
  • 3I0/7
  • 4I0/7
  • 5I0/7
  • 6I0/7
Find the intensity on the screen at O if S1 and S3 are covered.
  • I07
  • I07
  • I06
  • I06
A metallic beam having Young's modulus Y is supported at the two ends. It is loaded at the centre. The depression of the centre is proportional to
  • Y
  • 1/Y
  • Y2
  • 1/Y2
What happens when the applied load increases and upto breaking stress in the experiment to determine the Young's modulus of elasticity?
  • The area of wire goes in decreasing and wire extends and breaks.
  • The area of wire goes in increasing and wire breaks.
  • The wire extends and area remains constant.
  • The area remains same and wire length is also same.
Calculate the speed of sound in oxygen at 0C and 1 atm. (Bulk modulus of elasticity of O2 is 1.41×105 Pa and density is 1.43 kg/m3)
  • 300 m/s
  • 340 m/s
  • 314 m/s
  • none of these
Which of the following substances has the highest value of the young's modulus?
  • Steel
  • Rubber
  • wood
  • Plastic
The isothermal bulk modulus of a gas at atmospheric pressure is
  • 1 mm of Hg
  • 13.6 mm of Hg
  • 1.013×105N/m2
  • none of these
A wire of mass M, density ρ and radius R is stretched. If r is the change in the radius and l is the change in its length, then Poisson's ratio is given by :
  • πlρMrR3
  • RMπlρr3
  • rMπlρR3
  • lMπlρR3
Two wires of equal length and cross-section area suspended as shown in figure. Their Young's modulus areY1 and Y2 respectively. The equivalent Young's modulus will be
1422549_a6d985a9ebd045e9b3919e31606f66a9.png
  • Y1+Y2
  • Y1+Y22
  • Y1Y2Y1+Y2
  • Y1Y2
A thin ring of radius R is made up of a material of density ρ and young's modulus Y. If the ring is rotated about its centre in its own plane with an angular velocity ω then the small increase in radius (ΔR) of the ring  is
  • ρω2R3Y
  • ρω2YR3
  • Yρω2R3
  • None
The Young's modulus of a wire is numerically equal to the stress which will
  • not charge the length of the wire
  • double the length of the wire
  • increase the length by 50%
  • charge the radius of the wire to half
The SI unit of stress is same as the SI unit of 
  • Strain
  • Modulus of elasticity
  • Pressure
  • Both (2) and (3)
A 1000 kg lift is tied with metallic wires of maximum safe stress of 1.4×108N/m2. If the maximum acceleration of the lift is 1.2cm2, then the minimum diameter of the wire is 
  • 0.01m
  • 0.01cm
  • 0.001m
  • 0.02cm
Two wires of different material and radius have their length in ratio of 1:2. if these were stretched by the same force, the strain produced will be in the ratio.  
  • 4 : 1
  • 1 : 1
  • 2 : 1
  • 1 : 2
The bulk modulus of elasticity for a monoatomic ideal gas during an isothermal process is (P = pressure of the gas) 
  • P
  • \dfrac{2P}3
  • \dfrac{5P}{3}
  • \dfrac{7P}{5}
Statement I:- Bulk modulus of an ideal fluid is infinite.
Statement II:- An ideal fluid is compressible.

  • Statement I is true,statement II is true and statement II is a correct explanation for statement I.
  • Statement I is true,statement IIis true and statement II is NOT the correct explanation for statement I.
  • Statement I is true, statement II is false.
  • Statement I is false,statement II is true.
A telephone wire between the two poles is 50 m long and 1 mm in radius.When it is stretched by a load of 65 kg,its length becomes 50.12 m.Calculate Young's modulus of elasticity.
  • 4.22\times10^{10} Nm^{-2}
  • 8.44\times10^{10} Nm^{-2}
  • 4.22\times10^{9} Nm^{-2}
  • 8.44\times10^{9} Nm^{-2}
Pick up the correct statement:
  • Cubic crystals exhibit isotropic nature with respect to therma expansion
  • Anisotropic solids expand in one direction and contract in perpendicular direction
  • Many of the crystals are anisotropic solids
  • Rock salt crystal exhibits isotropic nature with respect to thermal expansion
0:0:1


Answered Not Answered Not Visited Correct : 0 Incorrect : 0

Practice Class 11 Engineering Physics Quiz Questions and Answers