An insulated rigid vessel contains a mixture of fuel and air. The mixture is ignited by a minute spark. The contents of vessel experience
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An insulated rigid vessel contains a mixture of fuel and air. The mixture is ignited by a minute spark. The contents of vessel experience
The specific heat of ideal gas depend on
Thermal power plant works on
In an isothermal process, the internal energy of molecules
For reversible adiabatic process, change in entropy is
A cylinder contains 5 m$$^3$$ of an ideal gas at a pressure of 1. This gas is compressed in a reversible isothermal process till its pressure increases to 5 bar. The work in kJ
required for this process is
A steel ball of mass 1 kg and specific heat 0.4 kj/kg is at a temperature of 60 deg C. It is dropped into 1 kg of water at 20 deg C. The final steady temperature of water is
A Bell-Coleman cycle is a reversed
A free bar of length l is uniformly heated from $$0^\circ C$$ to a temperature $$t^\circ C$$. $$\alpha$$ is the coefficient of linear expansion and E is the modulus of elasticity. The stress in the bar is
The materials having same elastic properties in all directions are called
A large cylindrical vessel was sealed in summer. What is likely to happen to it in winter?
A concentrated load P acts on a simply supported beam of span L at a distance of $$\frac{L}{3}$$ from left support. The bending moment at the point of application of load is given by
Moment of inertia (about its neutral axis) of hollow rectangular section with overall width and depth as B and D and hollow rectangular hole as b and d is
Neutral plane of the beam
Section modulus is defined as
Maximum deflection in a beam of span l supported freely at both ends due to central load P at middle with Young’s modulus E and moment of inertia I is
For a given material, Young’s modulus = 200GN/m$$^2$$ and modulus of rigidity = 80GN/m$$^2$$ . Its bulk modulus will be
A hollow shaft of 20 mm diameter and 16 mm inside diameter is subjected to a torque of 40 Nm. The shear stress at outside of the shaft will be:
If two shafts of same length, one of which is hollow, transmit equal torques and have equal maximum stress, then they should have equal
Carbon content of mild steel can be
There are fourteen atoms in a unit cell of
An alloy of copper, tin and zinc is known as
Cast iron and steel pipes are produced by
Electron beam welding can be carried out in
The welding process used to join ends of two pipes of uniform cross section is
For a Newtonian fluid
Oil in a hydraulic cylinder is compressed from an initial volume 2 m$$^3$$ to 1.96 m$$^3$$ and the pressure increase is from 40 MPa to 80 MPa. The bulk modulus of elasticity of oil is
Pitot tube is used for measurement of
For laminar flow through a long pipe, the pressure drop per unit length is
Oil flows through 200 mm diameter horizontal cast iron pipe with friction factor of 0.0225 of length 500 mtr. The volumetric flow rate is 0.2 m$$^3$$/sec. The head loss in mtr.
due to friction will be
A hydraulic turbine develops 1000 kW power for a head of 40 m. If the head is reduced to 20 m, power developed in kW is
Impulse turbine is used for
Laminar flow occurs in pipes, when Reynolds number is
Power in kW required to drive Centrifugal pump with discharge of Q m$$^3$$/sec, Head in H mtr, specific weight of fluid as $$\omega N/m^3$$ and overall efficiency of pump as $$\eta$$ shall be
If the net positive section head(NPSH) for the pump is not satisfied, then
For a given heat flow and for the same thickness, the temperature drop across material will be maximum for
The rate of heat flow through a body is $$Q = \frac{kA(T_1 - T_2)}{x}$$, the term, $$\frac{x}{kA}$$ is known as
A furnace made of a red brick wall of thickness 0.5 mtr. and conductivity 0.7 W/mK is replaced by alternate material of conductivity 0.14 W/mK. For the same heat loss and
temperature drop, required thickness of alternate material will be
The concept of overall coefficient of heat transfer is used in calculating heat transfer by
With an increase in the thickness of insulation around a circular pipe, heat loss to surroundings due to
A long glass cylinder of inner diameter 0.03 m and outer diameter 0.05 m carries hot fluid inside. If the thermal conductivity of glass is 1.05 W/mK, the thermal resistance
per unit length of the cylinder is
In heat exchangers, degree of approach is defined as the difference between temperatures of
In counter flow heat exchangers between two fluids,
Log mean temperature difference in case of counter flow heat exchanger compared to parallel flow heat exchanger will be :
The emissive power of a body depends on:
The outside diameter of hollow shaft is twice that of its inside diameter. The ratio of its torque carrying capacity to that of solid shaft of the same material and same outside diameter is :
The designation M 33 $$\times$$ 2 of a bolt means
The power transmitted by means of belt drives depends upon :
The usual proportion for the width of the key used between shaft (of diameter d) and hub of pulley for transmitting power is
The helix angle for single helical gears ranges from
The air standard efficiency of a standard otto cycle for compression ratio of 5.5 is
The power actually developed by the engine cylinder of an I.C engine is known as
In a boiler, feed water is supplied per hour is 205 kg while coal fired per hour is 23 kg. Net enthalpy rise per kg of water is 145 kJ for conversion to steam. If the calorific
value of coal is 2050 kJ/kg, boiler efficiency will be
Which of the following power plant is least polluting and causing least environmental concern?
A diesel power station has fuel consumption of 0.2 kg per kWh. If the calorific value of diesel is 11000 kcal per kg, overall efficiency of power station is
In aircraft, air refrigeration is used because of
A reversible engine has ideal thermal efficiency of 30%. When it is used as refrigerating machine with all other conditions unchanged, the coefficient of performance will be
In Vapour compression system, the condition of refrigerant before passing through the condenser is
Lithium bromide in vapour absorption refrigeration system is used as
In refrigeration cycle, sub cooling occurs when
For air with a relative humidity of 80%
During evaporative cooling process, wet bulb temperature
In a psychrometric process, the sensible heat added is 30 kJ/sec and latent heat added is 20 kJ/sec. The sensible heat factor for the process is
The bypass factor of cooling coil decreases with
The wet bulb depression is zero when relative humidity is
In the metal cutting process, the high cutting speed and large angle of the tool will result in the formation of
Gear hobbing produces more accurate gears than milling, because in hobbing
The type of tool used in milling machine and broaching machine is
The Ackerman steering gear mechanism is preferred to Davis steering mechanism because
The natural frequency of free torsional vibrations of a shaft with torsional stiffness q and I is the mass moment of inertia of the disc attached to the end of the shaft is
A is a 3 $$\times$$ 4 real matrix and Ax = b is a consistent system of equations. The highest possible rank of A is
The value of the quantity P where $$P = \int_{0}^{1} xe^x dx$$ is equal to
The solution of the differential equation $$\frac{dy}{dx} = \frac{-x}{y}$$ at $$x = 1$$ and $$y = \sqrt(3)$$ is
The analytic function $$f(z) = \frac{z - 1}{z^2 + 1}$$ has singularities at
X is a uniformly distributed random variable that takes value between 0 and 1. The value of E(X$$^3$$) will be
The equation $$e^x − 1 = 0$$ is required to be solved using Newton’s method with an initial guess of $$x_0 = −1$$. Then after one step of Newton’s method, the estimate $$x_1$$ of the solution will be
Laplace transform of $$f(t) = t^2 \sin t$$ is
The residue of a complex function $$x(z) = \frac{1 - 2z}{z(z - 1)(z - 2)}$$ at its poles are
The solution of the differential equation $$\frac{dy}{dx} + y^2 = 0$$ is
A box contains 10 screws, 3 of which are defective. Two screws are drawn at random with replacement. The probability that none of the two screws will be defective is:
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