The process is adiabatic, if the value of n in the equation pvn = C, is
0
1
γ
∝
Correct Answer :
C. γ
Related Questions
The given figure shows the Mohr's circle of stress for two unequal and like principal stresses (σx and σy) acting at a body across two mutually perpendicular planes. The normal stress on an oblique section making an angle θ with the minor principle plane is given by
OC
OP
OQ
PQ
In the below figure, curve D represents_________.
Mild steel
Cast iron
Concrete
Bone of these
Diesel cycle consists of __________ processes.
Two constant volume and two isentropic
Two constant pressure and two isentropic
Two constant volume and two isothermal
One constant pressure, one constant volume and two isentropic
The atomic mass of oxygen is
12
14
16
32
Which of the following is the extensive property of a thermodynamic system?
Pressure
Volume
Temperature
Density
Percentage reduction in area performing tensile test on cast iron may be of the order of
50 %
25 %
20 %
30 %
A concentrated load is one which
Acts at a point on a beam
Spreads non-uniformly over the whole length of a beam
Spreads uniformly over the whole length of a beam
Varies uniformly over the whole length of a beam
The absolute zero pressure will be
When molecular momentum of the system becomes zero
At sea level
At the temperature of - 273 K
At the centre of the earth
The state of a substance whose evaporation from its liquid state is complete, is known as
Vapour
Perfect gas
Air
Steam
The efficiency of the Carnot cycle is (where T1 and T2 = Highest and lowest temperature during the cycle)
(T1/T2) - 1
1 - (T1/T2)
1 - (T2/T1)
1 + (T2/T1)
The extension of a circular bar tapering uniformly from diameter d₁ at one end to diameter d₂ at the other end and subjected to an axial pull of P is given by
δl = 4PE/ πl²
δl = 4πld²/PE
δl = 4Pl/πEd₁d₂
δl = 4PlE/ πd₁d₂
When a body is subjected to biaxial stress i.e. direct stresses (σx) and (σy) in two mutually perpendicular planes accompanied by a simple shear stress (τxy), then minimum normal stress is
(σx + σy)/2 + (1/2) × √[(σx - σy)² + 4 τ²xy]
(σx + σy)/2 - (1/2) × √[(σx - σy)² + 4 τ²xy]
(σx - σy)/2 + (1/2) × √[(σx + σy)² + 4 τ²xy]
(σx - σy)/2 - (1/2) × √[(σx + σy)² + 4 τ²xy]
In an ideal gas turbine plant, it is assumed that the compression and expansion processes are
Isothermal
Isentropic
Polytropic
None of these
The efficiency and work ratio of a simple gas turbine cycle are
Very low
Low
High
Very high
Relation between cp and cv is given by (where cp = Specific heat at constant pressure, cv = Specific heat at constant volume, γ = cp/cv, known as adiabatic index, and R = Gas constant)
cv/ cp =R
cp - cv = R
cv = R/ γ-1
Both (B) and (C)
The efficiency and work ratio of a simple gas turbine cycle are
Low
Very low
High
Very high
For the same compression ratio, the efficiency of dual combustion cycle is
Greater than Diesel cycle and less than Otto cycle
Less than Diesel cycle and greater than Otto cycle
Greater than Diesel cycle
Less than Diesel cycle
The heat energy stored in the gas and used for raising the temperature of the gas is known as
External energy
Internal energy
Kinetic energy
Molecular energy
Which of the following statement is correct?
The heat and work are boundary phenomena
The heat and work represent the energy crossing the boundary of the system
The heat and work are path functions
All of the above
The reading of the pressure gauge fitted on a vessel is 25 bar. The atmospheric pressure is 1.03 bar and the value of 'g' is 9.81 m/s2. The absolute pressure in the vessel is
23.97 bar
25 bar
26.03 bar
34.81 bar
Second law of thermodynamics defines
Heat
Work
Internal energy
Entropy
The ratio of elongation in a prismatic bar due to its own weight (W) as compared to another similar bar carrying an additional weight (W) will be
1 : 2
1 : 3
1 : 4
1 : 2.5
Otto cycle consists of following four processes
Two isothermals and two isentropic
Two isentropic and two constant volumes
Two isentropic, one constant volume and one constant pressure
Two isentropic and two constant pressures
The value of specific heat at constant pressure (cp) is __________ that of at constant volume (cv).
Less than
Equal to
More than
None of these
The property of a material which allows it to be drawn into a smaller section is called
Plasticity
Ductility
Elasticity
Malleability
The most probable velocity of the gas molecules is given by
√(KT/m)
√(2KT/m)
√(3KT/m)
√(5KT/m)
The thermodynamic difference between a Rankine cycle working with saturated steam and the Carnot cycle is that
Carnot cycle can't work with saturated steam
Heat is supplied to water at temperature below the maximum temperature of the cycle
A Rankine cycle receives heat at two places
Rankine cycle is hypothetical
The compression ratio is the ratio of
Swept volume to total volume
Total volume to swept volume
Swept volume to clearance volume
Total volume to clearance volume
When a gas is heated, change takes place in
Pressure
Volume
Temperature
All of these
The ultimate tensile stress of mild steel compared to ultimate compressive stress is
Same
More
Less
Unpredictable