Question 1 :
Assertion: If we apply force to a lump of putty or mud, they have no gross tendency to regain their previous shape.
Reason: This type of substances are called plastic substances.
Question 2 :
A compressive force is applied to a uniform rod of rectangular cross-section so that its length decreases by $1\%$. If the Poisson’s ratio for the material of the rod be $0.2$, which of the following statements is correct ? The volume approximately .....”
Question 3 :
Assertion: The strain present in the material after unloading is called the residual strain or plastic strain and the strain disappears during unloading is termed as recoverable or elastic strain.
Reason: After yieild point, there is some residual stress left in an material on unloading.
Question 4 :
A material has poisson's ratio 0.5. If a uniform rod of it suffers a longitudinal strain of $3\times { 10 }^{ -3 }$, what will be percentage increase in volume?
Question 5 :
When a body undergoes a linear tensile strain if experience a lateral contraction also. The ratio of lateral contraction to longitudinal strain is known as
Question 6 :
Assertion: Strain is a unitless quantity.
Reason: Strain is equivalent to force
Question 8 :
Let ${Y}_{S}$ and ${Y}_{A}$ represent Young's modulus for steel and aluminium respectively It is said that steel is more elastic than aluminium. Therefore, it follows that
Question 9 :
A wire ($Y=2\times {10}^{11}N/m$) has length $1m$ and area $1m{m}^{2}$. The work required to increased its length by $2mm$ is
Question 11 :
When a rubber cord is stretched, the change in volume is negligible compared to the change in its linear dimension. Then poisson's ratio for rubber is
Question 12 :
The compressibility of water is $\displaystyle 46.4\times 10^{-6}/atm $ This means that
Question 14 :
 A cable that can support a load of 1000 N is cut into equal parts. the maximum load that can be supported by the either part is:-
Question 15 :
The Young's modulus of a wire of length $L$ and radius $r$ is $Y$. If the length is reduced to $\cfrac{L}{2}$ and radius is $\cfrac{r}{2}$, then the Young's modulus will be
Question 16 :
There are two wires of same material. their radii and lengths are both in the ratio 1:2. if the extensions produced are equal, what is the ratio of the loads?
Question 17 :
Assertion: The stress-strain behaviour varies from material to material.
Reason: A rubber can be pulled to several times its original length and still returns to its original shape.
Question 18 :
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:
Question 19 :
A weightless rod is acted on by upward parallel forces of $2N$ and $4N$ ends $A$ and $B$ respectively.; The total length of the rod $AB=3m$. To keep the rod in equilibrium a force of $6N$ should act in the following manner.
Question 20 :
Assertion: Stress is the internal force per unit area of a body.
Reason: Rubber is more elastic than steel.
Question 21 :
A mass m is suspended from a wire. Change in length of the wire is $\Delta l$. Now the same wire is stretched to double its length and the same mass is suspended from the wire. The change in length in this case will become (it is assumed that elongation in the wire is within the proportional limit)
Question 22 :
The length of of a metal wire $l$ when the tension in is $'F'$ and $'xl'$ when the tension is $'yF'$. Then the natural length of the wire is
Question 23 :
The velocity of water in the river is $9km{/hr}$ of the upper surface. The river is $10$m deep. If the coefficient of viscosity of water is $10^{-2}$ poise then the shearing stress between horizontal layers of water is.<br/>
Question 24 :
The breaking stress of aluminium is $7.5\times {10}^{7}N{m}^{-2}$. The greatest length of aluminium wire that can hang vertically without breaking is<br>(Density of aluminium is $2.7\times {10}^{3}kg{m}^{-3}$)
Question 25 :
Assertion: If a metal wire is attached to the ceiling of a room and mass $m$ is attached to another end, the energy stored in the stretched wire is $mgl/2$ where $l$ is the increment in length of wire
Reason: In the above statement loss in gravitational energy is $mgl$ while the loss in energy to surrounding is $\dfrac{mgl}{2}$
Question 27 :
The elongation produced in a copper wire of length 2m and diameter 3mm, when a force of 30N is applied is [Y$=$1x10$^{11}$N.m$^{-2}$]
Question 28 :
For a given material, the Young's modulus is $2.4$ times that of rigidity modulus. Its poisson's ratio is.
Question 29 :
Assertion: Brittle materials, which includes cast iron, glass, and stone, are characterized by the fact that rupture occurs without any noticeable prior change in the rate of elongation.
Reason: There is no neck formation in stress strain curve for brittle material.
Question 30 :
A wire of length L and of cross-sectional area A is made of a material of Young's modulus Y. The work done in stretching the wire by an amount $x$ is given by :
Question 32 :
When a metal wire is stretched by a load, the fractional change in its volume $\Delta V/V$ is proportional to?
Question 33 :
A fixed volume of iron is drawn into a wire of length $l$. The extension produced in this wire by a constant force $F$ is proportional to :
Question 34 :
A metallic rod of length $l$ and cross sectional area $A$ is made of a material of Young's modulus $Y$. If the rod is elongated by an amount $y$, then the work done is proportional to
Question 35 :
A wire of initial length $L$ and radius $r$ is stretched by a length $l$. Another wire of same material but with initial length $2L$ and radius $2r$ is stretched by a length $2l$. The ratio of the stored elastic energy per unit volume in the first and second wire is,
Question 36 :
The theoretical limits of poisson's ratio lies between -1 to 0.5 because
Question 37 :
A copper wire of length $2.4m$ and a steel wire of length $1.6m$, both the diameter $3mm$, are connected end to end. The ratio fo elongation of steel to the copper wires is then<br/>$\left( { Y }_{ copper }=1.2\times { 10 }^{ 11 }N\quad { m }^{ -2 },{ Y }_{ steel }=2\times { 10 }^{ 11 }N\quad { m }^{ -2 } \right) $
Question 38 :
How much force is required to produce an increase of 0.2% in the length of a brass wire of diameter 0.6 mm? [Young modulus for brass $=0.9\times 10^{11}N/m^{2}$]:-<br>
Question 39 :
 A 2.0 cm cube of some substance has its upper face displaced by 0.15 cm , by a tangential force of 0.30 N fixing its lower face. Calculate the rigidity modulus of the substance.
Question 40 : <p>An iron rod of length 2m and cross- sectional area of $50mm^{2}$ stretched by 0.5mm, when a mass of 250 kg is hung from its lower end. Young's modulus of iron rod is </p>
Question 41 :
Young's moduli of two wires A and B are in the ratio $7 : 4$. Wire A is 2 m long and has radius R. Wire B is $1.5 m $ long and has radius 2 mm. If the two wires stretch by the same length for a given load, then the value of R is close to : :
Question 42 :
A steel wire 2 m long is suspended from the ceiling. When a mass is hung at its lower end, the increase in length recorded is 1 cm. Determine the strain in the wire.
Question 43 :
A steel rope has length $L$, area of cross-section $A$, Young's modulus $Y$. [$Density = d$]. If the steel rope is vertical and moving with the force acting vertically up at the upper end, find the strain at a point $\displaystyle \frac{L}{3}$ from lower end.
Question 44 :
If a rubber ball is taken down to a 100 m deep lake, its volume decreases by 0.1%. If $g=10\quad m/{ s }^{ 2 }$ then the bulk modulus of elasticity for rubber, in N/${ m }^{ 2 }$, is 
Question 45 :
The speed of a traverse wave travelling on a wire having a length $50\space cm$ and mass $50\space g$ is $80\space ms^{-1}$. The area of cross-section of the wire is $1\space mm^2$ and its Young's modulus is $16\times10^{11}\space Nm^{-2}$. Find the extension of the wire over natural length.
Question 46 :
The Poisson's ratio of the material of a wire is$0.25 .$ If it is stretched by a force F, the longitudinal strain produced in the wire is $5 \times 10 ^ { - 4 } .$ What is the percentage increase in its volume?
Question 47 :
In a Young's double slit experiment with sodium light, slits are 0.589 m apart. The angular separation of the maximum from the central maximum will be (given $\lambda =589$nm,):
Question 48 :
Two metal wire 'P' and 'Q' of same length and material are stretched by same load. Their masses are in the ratio $m_1 : m_2$. The ratio of elongations of wire 'P' to that of 'Q' is
Question 49 :
Two wires of the same radius and material and having length in the ratio $8.9:7.6$ are stretched by the same force. The strains produced in the two cases will be in the ratio:
Question 50 :
The Young's modulus of a material is $2\times { 10 }^{ 11 }N/{ m }^{ 2 }$ and its elastic limit is $1.8\times { 10 }^{ 8 }N/{ m }^{ 2 }$. For a wire of $1m$ length of this material, the maximum elongation achievable is
