250+ TOP MCQs on IC Engine – Stresses in Cylinder Wall and Answers

Automotive Engine Components Design Multiple Choice Questions on “IC Engine – Stresses in Cylinder Wall”.

1. Longitudinal stress doesn’t act on the cylinder.
a) True
b) False
Answer: b
Clarification: Circumferential hoop stress and the longitudinal stress are the two principal stresses that act on the engine cylinder. So, longitudinal stress act on the cylinder.

2. Calculate the net circumferential stress when σ_c=20N/mm², σ_I=11N/mm² and μ=0.2.
a) 17.8N/mm²
b) 16.5N/mm²
c) 16.5N/m²
d) 16.3N/mm³
Answer: a
Clarification: (σ_c)_net=σ_c-μσ_I
=20-0.2×11
=17.8N/mm²

3. Calculate the net longitudinal stress σ_c=20N/mm², σ_I=11N/mm² and μ=0.2
a) 6N/mm²
b) 7N/mm²
c) 8N/mm²
d) 9N/mm²
Answer: a
Clarification: (σ_I)_net=σ_I-μσ_c
=11-0.2×20
=7N/mm²

4. Calculate the net minimum outer diameter of the cylinder, when the inner diameter of the cylinder is 140mm and thickness is 11mm.
a) 153mm
b) 170mm
c) 160mm
d) 162mm
Answer: d
Clarification: D₀=D+2t
=140+2(11)
=162mm

5. Calculate the thickness of the cylinder when P_max=3MPa, D=150mm, C=4and σ_c=45N/mm².
a) 9mm
b) 6mm
c) 7mm
d) 8mm
Answer: a
Clarification: t=(frac{P_{max}times D}{2sigma})+C
=(frac{3×150}{2×45}+4)
=5+4
=9mm

6. Calculate the apparent circumferential stress, when P_max=3.5MPa, D=140mm, and t=8mm?
a) 12.3N/mm²
b) 14.4N/mm²
c) 15.3N/mm²
d) 16.1N/mm²
Answer: c
Clarification: σ c=(frac{P_{max}D}{2t})
=(frac{3.5×140}{2×16})
=15.3N/mm²

7. Calculate the apparent longitudinal stress when Do=162mm, D=140mm, Pmax=3MPa.
a) 8.85N/mm²
b) 9.32N/mm²
c) 6.66N/mm²
d) 7.65N/mm²
Answer: a
Clarification: σ_I=(frac{P_{max}D^2}{Do^2-D^2})
=(frac{3×140^2}{(162^2×140^2)})
=8.85N/mm²

8. In the formula (σ_I)_net=σ_I-μσ_c, what is µ?
a) Yield point
b) Hoop constant
c) Stress constant
d) Poisson’s ratio