Physics

Solid Mechanics

537 Questions

Solid mechanics questions evaluate the understanding of stress, strain, and material deformation under various loads. Topics include analyzing beams, cantilevers, and structural steel designs using specific industrial standards. These principles are strictly examined in engineering and civil services preliminary tests.

Stress and strainBeam analysisPrestressed concreteMaterial strengthStructural design

Solid Mechanics Questions

Multiple choice physics hooke's law

The maximum stress developed in the rod is equal to $(N/m^{2})$.

  1. $5\times 10^{7}$
  2. $5\times 10^{8}$
  3. $4\times 10^{7}$
  4. $4\times 10^{8}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Multiple choice physics hooke's law

Which of the following is/are true about deformation of a material?

  1. Deformation capacity of the plastic hinge and resilience of the connections are essential for good plastic behavior

  2. Deformation capacity equations considering yield stress and gradient of moment

  3. Different materials have different deformation capacity

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In well-designed steel frame structures, inelastic deformation under severe seismic loading is confirmed in beam plastic hinges located near the beam-to-column connections. Thus, deformation capacity of the plastic hinge and resilience of the connections are essential for good plastic behavior and expected energy dissipation in steel frame structures. This essential plastic behaviour at the hinge is strongly influenced by the difference of material properties. Generally, the material properties are specified in terms of yield stress and/or ultimate strength. However, the characteristics of the materials are not defined by only these properties. Thus, the characteristics of various materials aren’t reflected in present building codes, particularly on deformation capacity classification.

Multiple choice physics common machines kinds of simple machines inclined plane, wedge, screw and wheel and axle types of simple machines

If a nail requires 3 N force to insert into wood, then the value of force required to insert a screw into wood will be:

  1. Less than 3N

  2. Greater than 3N

  3. 3N

  4. Can't say
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A screw is preferred over a nail to insert into wood because it requires lesser force to insert. Therefore the value of force required to insert a screw in the given question is less than 3 N.

Multiple choice forces on solids elastic and plastic substances forces and matter properties of matter physics

A uniform steel bar of cross-sectional area A and length L. is suspended so that it hangs vertically. The stress at the middle point of the bar is ( $\rho $ is the density of steel)

  1. $\frac{L}{2A} \rho g$
  2. $\frac{L\rho g}{2} $
  3. $\frac{LA}{\rho g}$
  4. $L\rho g$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The stress at any point in a hanging bar is caused by the weight of the portion of the bar hanging below that point. At the middle point, the length of the bar suspended below is L/2, so the weight of that section is (L/2) * A * rho * g. Dividing this force by the cross-sectional area A yields the stress as (L * rho * g) / 2.

Multiple choice forces on solids elastic and plastic substances forces and matter properties of matter physics

If equal and opposite forces applied to a body tend to elongate it, the stress so produced is called

  1. Tensile stress

  2. Compressive stress

  3. Tangential stress

  4. Working stress
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Tensile stress occurs when equal and opposite forces act to pull or elongate a body. Compressive stress occurs when forces act to shorten a body.

Multiple choice forces on solids elastic and plastic substances forces and matter properties of matter physics

A steel rod of length $5\ m$ is fixed rigidly between two supports, $\alpha$ of steel$=12\times 10^{-6}/^{o}\ C$, $Y=2\times10^{12}Nm^{-2}$. With the increase in its temperature by $40^{o}\ C$, the stress developed in the rod is

  1. $9.6\times10^{5}\ Nm^{-2}$
  2. $9.6\times10^{6}\ Nm^{-2}$
  3. $9.6\times10^{7}\ Nm^{-2}$
  4. $9.6\times10^{8}\ Nm^{-2}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Thermal stress developed in a rigidly fixed rod is given by the formula stress = Y * alpha * delta T. Substituting Y = 2 * 10^12 Nm^-2, alpha = 12 * 10^-6 /C, and delta T = 40 C gives 9.6 * 10^8 Nm^-2.

Multiple choice forces on solids elastic and plastic substances forces and matter properties of matter physics

A bar of cross-section A is subjected to equal and opposite tensile forces at its ends. Consider a plane section of the bar whose normal makes an angle $\theta$ with the axis of the bar.
For what value of $\theta$ is the tensile stress maximum?

  1. 0

  2. 1

  3. cant say

  4. 90
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Tensile stress$=\cfrac { force }{ area } =\cfrac { F\cos { \theta  }  }{ A\sec { \theta  }  } $
$=\cfrac { F }{ A } \cos ^{ 2 }{ \theta  } $
Tensile strength will be maximum when $\cos ^{ 2 }{ \theta  } $ is maximum i.e., $\cos { \theta  } =1$ or $\theta =0°$
Multiple choice forces on solids elastic and plastic substances forces and matter properties of matter physics

A steel rod of length $1m$ and radius $10mm$ is stretched by a force $100kN$ along its length. The stress produced in the rod is then
 $\left( { Y } _{ steel }=2\times { 10 }^{ 11 }N\quad { m }^{ -2 } \right) $

  1. $3.18\times { 10 }^{ 6 }N\quad { m }^{ -2 }$
  2. $3.18\times { 10 }^{ 7 }N\quad { m }^{ -2 }\quad $
  3. $3.18\times { 10 }^{ 8 }N\quad { m }^{ -2 }$
  4. $3.18\times { 10 }^{ 9 }N\quad { m }^{ -2 }\quad $
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Here $r=10mm=10\times { 10 }^{ -3 }m={ 10 }^{ -2 }m$
$L=1m,F=100kN=100\times { 10 }^{ 3 }N={ 10 }^{ 5 }N$

Stress produced in the rod is:
$Stress=\cfrac { F }{ A } =\cfrac { F }{ \pi { r }^{ 2 } } =\cfrac { 100\times { 10 }^{ 3 }N }{ 3.14\times { \left( { 10 }^{ -2 }m \right)  }^{ 2 } } =3.18\times { 10 }^{ 8 }N\quad { m }^{ -2 }\quad $

Multiple choice physics turning on a pivot the turning effect of a force moment of force or torque turning effect of force couple

Consider a cylindrical shaft of length $\lambda$ and radius $R$. It is twisted by torque r. If shear modulus of material is $S$, then angle of twist should be.

  1. $\theta =\dfrac { \pi SR^{ 4 } }{ 2\tau \ell } $
  2. $\theta =\dfrac { 2\tau }{ \pi S\ell S^{ 4 } } $
  3. $\theta =\dfrac { 2\tau \ell }{ \pi SR^{ 2 } } $
  4. $\theta =\dfrac { 2\tau \ell }{ \pi SR^{ 4 } } $
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The formula for the angle of twist in a cylindrical shaft is theta = (2 * torque * length) / (pi * shear_modulus * radius^4).

Multiple choice chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

Which of the following statements is incorrect?

  1. When a material is under tensile stress, the restoring forces are caused by interatomic attraction while under compressional stress, the restoring force is due to interatomic repulsion

  2. The stretching of a coil is determined by its shear modulus

  3. Rubber is more elastic than steel

  4. Shearing stress plays an important role in the buckling of shafts
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

More elastic means, the value of an elastic constant is more and. Steel have move elastic constant in compare to Rubber, So Steel is more elastic than rubber.
All other statements are correct.

Multiple choice chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

As compared to concrete, steel has compressive strength:

  1. $25$ times less

  2. equal
  3. $25$ times more
  4. $5$ times more
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Compressive strength is the capacity of a material or structure to withstand loads tending to reduce size, as opposed to tensile strength, which withstands loads tending to elongate.

Compressive strength is one of the most important engineering property of Concrete which designers are concerned of. However the compressive strength of steel is around 25 time more than that of concrete.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

The property of a material due to which shape is changed permanently is known as:

  1. Elasticity

  2. Plasticity

  3. Ductility

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The property of a body to regain its original shape when the deforming force is removed from it or to oppose the change in its original shape is called elasticity.

Plasticity is the property of a material not to regain its original shape when the deforming force is removed, i e. a deforming force changes the shape of material permanently. 
Ductility is commonly defined as the ability of a body to be stretched into wires.

Multiple choice chemistry substances in the surroundings - their states and properties elastic behaviour of solids elastic and plastic substances properties of substances

Elasticity is defined as the ability of a body to 

  1. Resist linear motion in a hard surface

  2. Resist rolling motion in a hard surface

  3. Resist a distorting influence and to return to its original size and shape when that influence or force is removed.

  4. Resist electric current in a magnetic field
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Elasticity is defined as the ability of a body to  resist a distorting influence and to return to its original size and shape when that influence or force is removed.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

 Plastic deformation results from the following 

  1. Slip

  2. Twinning

  3. Both slip and twinning

  4. creep
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Two prominent mechanisms of plastic deformation, namely slip and twinning occur . 
1. Slip involves sliding of blocks of crystal over one other along definite crystallographic planes, called slip planes. During slip each atom usually moves same integral number of atomic distances along the slip plane producing a step, but the orientation of the crystal remains the same.

2. Portion of crystal takes up an orientation that is related to the orientation of the rest of the untwined lattice in a definite, symmetrical way. The twinned portion of the crystal is a mirror image of the parent crystal.

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

Plastic deformation in a material begins at

  1. Q point

  2. Yield point

  3. Proportionality limit

  4. Elastic limit
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Beyond the elastic limit, permanent deformation will occur. The elastic limit is therefore the lowest stress point at which permanent deformation can be measured. At yield point, permanent deformation occurs or the substance becomes plastic.

The correct option is option (b)