Physics

Solid Mechanics

510 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 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)

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

The materials, which do not show a fixed trend of deformation vs. applied force, are called:

  1. inelastic materials

  2. plastic materials

  3. elastic materials

  4. rigid materials
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Elastic materials are those that follow the Hooke's law, which is that the deformation produced in a material is directly proportional to the stress applied to it, and the material is recoverable after the deformation force is removed.

Inelastic materials are those that do not follow this relationship. They do not show a fixed trend of deformation vs applied force; in fact, they might not deform at all (rigid materials) or the deformation observed is not completely recoverable.

Multiple choice physics current electricity meter bridge meter bridge and problems on it galvanometer

In a Wheatstone's bridge, there resistances P, Q and R connected in the three arms and the fourth arm is formed by two resistances $S _1$ and $S _2$ connected in parallel. The condition for bridge to be balanced will be :

  1. $\dfrac{P}{Q}=\dfrac{R}{S _1+S _2}$
  2. $\dfrac{P}{Q}=\dfrac{2R}{S _1+S _2}$
  3. $\dfrac{P}{Q}=\dfrac{R(S _1+S _2)}{S _1S _2}$
  4. $\dfrac{P}{Q}=\dfrac{R(S _1+S _2)}{2S _1S _2}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$\dfrac{P}{Q}=\dfrac{R}{S}$

$=\dfrac{R(S _1+S _2)}{S _1S _2}$. wher S is the equivalent resistance of $S _1 and S _2$

Multiple choice physics effects of electric current meter bridge meter bridge and problems on it galvanometer

In the experiment of half deflection method the resistance R should be

  1. > S
  2. $\approx$ S

  3. < S
  4. $\approx$ G
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In half deflection method, Rg = (R)*(S)/(R-S) .
Here , Rg= Galvanometer resistance, R = high resistance in series with the galvanometer, S = low resistance in parallel with the galvanometer. We want to approximate Rg in terms of S which we are able to vary in the experiment . If R>>S then Rg = S.                                      

Multiple choice physics current electricity meter bridge meter bridge and problems on it galvanometer

In a Wheatstone bridge, three resistances P, Q and R are connected in the three arms and the fourth arm is formed by two resistances $S _1$ and $S _2$ connected in parallel. The condition for the bridge to be balanced will be

  1. $\displaystyle \frac{P}{Q} = \frac{R(S _1 + S _2)}{2S _1S _2}$
  2. $\displaystyle \frac{P}{Q} = \frac{R}{S _1 + S _2}$
  3. $\displaystyle \frac{P}{Q} = \frac{2R}{S _1 + S _2}$
  4. $\displaystyle \frac{P}{Q} = \frac{R(S _1 + S _2)}{S _1S _2}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The balanced condition for Wheatstone bridge is  $\dfrac{P}{Q}=\dfrac{R}{S}$

Here $S=\frac{S _1S _2}{S _1+S _2}$  (as $S _1$ and $S _2$ are connected in parallel in S arm)
so, $\dfrac{P}{Q}=\dfrac{R(S _1+S _2)}{S _1S _2}$

Multiple choice physics heat and temperature anomalous expansion of water thermal expansion in solids, liquids and gases thermal expansion

While laying the railway tracks on wooden plank,a small gap is left between the successive lengths of rail because

  1. It no gap is left, the expansion of rails will cause them to bend sideways

  2. If no gap is left, the expansion will break the rails

  3. If no gap is left, rails decrease in length

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

The rails of railway tracks are made up of steel.in summer,due to considerable rise in atmospheric temperature, the rails tend to increase in length,so they bend sideways if they are not allowed to increase in length.therefore while laying the railway tracks on wooden plank,a small gap is left between the successive lengths of rail.

Multiple choice elastic energy properties of material substances elasticity properties of matter physics

The total strain energy stored in a body is known as 

  1. Resilience

  2. Toughness

  3. Modulus of resilience

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

The strain energy is released when the object is unloaded, which is nothing but resilience

Resilience is the ability of a material to absorb energy when deformed, and release that energy upon unloading

The correct option is (a)

Multiple choice elastic energy properties of material substances elasticity properties of matter physics

Four identical hollow cylindrical columns of steel support a big structure of mass $50,000kg$. The inner and outer radii of each column are $30\ cm$ and $60\ cm$ respectively, Assuming the load distribution to be uniform. Calculate the compressional strain of each column,

  1. $7.2\times 10^{-7}$
  2. $3.78\times 10^{-6}$
  3. $2.78\times 10^{-4}$
  4. $3.78\times 10^{-4}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Strain = Stress / Y. Stress = Force / Area. Force = (50000 * 9.8) / 4 columns. Area = pi * (R^2 - r^2). Using Y = 2e11 Pa for steel, the calculation yields approximately 7.2e-7.

Multiple choice elastic energy properties of material substances elasticity properties of matter physics

A composite rodd consists of a steel rod of length $25cm$ and area $2A$ and a copper rod of length $50cm$ and area $A$. The composite rod is subjected to an axial load $F$. If the Young's modulii of steel and copper are in the ration $2:1$, then

  1. The extension produced in copper rod will be more
  2. The extension in copper and steel parts will be in the ratio $1 : 2$

  3. The stress applied to copper rod will be more

  4. No extension will be produced in the steel rod
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation
$Stress=\dfrac{Force}{Area}$. Since force applied on both materials is same, but area of steel is more, so stress for copper will be more.
$\Delta l=\dfrac { FL }{ AY } $
Force is same for both.
Thus, $Extension,\Delta l \propto \dfrac{l}{AY}$
Thus$\dfrac{{\Delta l} _{Steel}}{{\Delta l} _{Copper}} \propto \dfrac{{(\dfrac{l}{AY})} _{Steel}}{{(\dfrac{l}{AY})} _{Copper}}$
=$\dfrac{{(\dfrac{25}{2A.2Y})}}{{(\dfrac{50}{AY})}}=1:8$
Multiple choice botany water absorption and ascent of sap in plants factors affecting the transport of water and minerals in plants ascent of sap long distance transport of water

Ability to rise in thin tubes and ability to resist pulling force are ................ and  .................. respectively 

  1. Tensile strength and capillarity.

  2. Cohesion and adhesion

  3. Capillarity and tensile strength

  4. Adhesion and capillarity
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Capillarity is the ability of water to rise through thin tubes.

The tensile strength of a substance is how well it can resist external force and maintain it's properties.
Cohesion is the attraction of two same particles.
Adhesion is the attraction of two different particles. 
So the correct answer is 'Capillarity and tensile strength'.

Multiple choice physics motion and measurement physical quantities units - definitions and systems physical quantities like mass and weight

Which one of the following does not have unit of force per unit area:

  1. $Stress$
  2. $Strain$
  3. $Youngs Modulus$
  4. $pressure$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • Stress  is the force per unit area on a body that tries to cause a change in shape. It is measured by the SI unit is Pascal.

  • Strain is defined as the deformation produced in a solid due to stress. It is measured by calculating the ratio of the two lengths. As a result it does not have any unit.  

  • Force is measured by the product of mass and acceleration. Its SI unit is Newton.

  • Pressure is measured by force per unit area. Its SI unit is Pascal.

So correct answer is option (B).