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

The stiffness coefficient kij indicates

  1. force at i due to a unit deformation at j

  2. deformation at j due to a unit force at i

  3. deformation at i due to a unit force at j

  4. force at j due to a unit deformation at i
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Stiffness coefficient $K_{ij} =$ Force required to produce unit deformation and $K_ij$ means force required in i for unit deformation at j.

Multiple choice

U1 and U2 are the strain energies stored in a prismatic bar due to axial tensile forces P1 and P2 respectively. The strain energy stored in the same bar due to combined action of P1 and P2 will be

  1. U = U1 + U2

  2. U = U1 U2

  3. U < U1 + U2

  4. U > U1 + U2
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Strain energy is proportional to the square of the force (U = P^2L/2AE). When two forces act simultaneously, the total energy is U = (P1+P2)^2 * L/2AE = (P1^2 + P2^2 + 2P1P2) * L/2AE = U1 + U2 + (2P1P2 * L/2AE). Since P1 and P2 are positive, the term 2P1P2 is positive, making U > U1 + U2.

Multiple choice

The width of the expansion joint is 20 mm in a cement concrete pavement. The laying temperature is 20°C and the maximum slab temperature in summer is 60°C. The coefficient of thermal expansion of concrete is 10 x 10–6 mm/mm/°C and the joint filler compresses upto 50% of the thickness. The spacing between expansion joints should be

  1. 20 m

  2. 25 m

  3. 30 m

  4. 40 m
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Expansion joint spacing L = (delta) / (alpha * deltaT). delta = 20mm * 0.5 = 10mm. alpha = 10 * 10^-6. deltaT = 60 - 20 = 40. L = 10 / (10 * 10^-6 * 40) = 10 / 0.0004 = 25,000 mm = 25 m.

Multiple choice

A singly reinforced rectangular concrete beam has a width of 150 mm and an effective depth of 330 mm. The characteristic compressive strength of concrete is 20 MPa. Adopt the stress block for concrete as given in IS 456-2000 and take limiting value of depth of neutral axis as 0.48 times the effective depth of the beam.

The limiting value of the moment of resistance of the beam in kNm is

  1. 0.14

  2. 0.45

  3. 45.08

  4. 156.82
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The limiting moment of resistance for a singly reinforced rectangular beam is calculated using the formula Mu,lim = 0.36 * fck * b * xu,lim * (d - 0.42 * xu,lim). Substituting the given values (b = 150 mm, d = 330 mm, fck = 20 MPa, xu,lim = 0.48 * d) yields approximately 45.08 kNm.