The compression ratio for Diesel engines is
3 to 6
5 to 8
15 to 20
20 to 30
Correct Answer :
C. 15 to 20
Related Questions
Which of the following statement is incorrect?
The liquid fuels have higher calorific value than solid fuels
The solid fuels have higher calorific value than liquid fuels
A good fuel should have low ignition point
The liquid fuels consist of hydrocarbons
The stress at which extension of the material takes place more quickly as compared to the increase in load is called
Elastic point of the material
Plastic point of the material
Breaking point of the material
Yielding point of the material
If the value of n = 0 in the equation pvn = C, then the process is called
Constant volume process
Adiabatic process
Constant pressure process
Isothermal process
The entropy may be expressed as a function of
Pressure and temperature
Temperature and volume
Heat and work
All of these
For the beam shown in the below figure, the shear force diagram between A and B is
A horizontal line
A vertical line
An inclined line
A parabolic curve
The efficiency of a Carnot engine depends on
Working substance
Design of engine
Size of engine
Temperatures of source and sink
A body is subjected to a tensile stress of 1200 MPa on one plane and another tensile stress of 600 MPa on a plane at right angles to the former. It is also subjected to a shear stress of 400 MPa on the same planes. The maximum normal stress will be
400 MPa
500 MPa
900 MPa
1400 MPa
In order to prevent crushing of masonry at the base of the dam, the maximum stress should be __________ the permissible stress of the soil.
Equal to
Less than
More than
None of these
One kg of carbon produces __________ kg of carbon dioxide.
3/7
7/3
11/3
3/11
For a simply supported beam of length l, when a concentrated load W is applied in the centre of the beam, the maximum deflection is
5WL³/ 384EI
WL³/384EI
WL³/ 348EI
WL³/ 48EI
Two shafts 'A' and 'B' transmit the same power. The speed of shaft 'A' is 250 r.p.m. and that of shaft 'B' is 300 r.p.m.
The shaft 'B' has the greater diameter
The shaft 'A' has the greater diameter
Both are of same diameter
None of these
The columns whose slenderness ratio is less than 80, are known as
Short columns
Long columns
Weak columns
Medium columns
Stirling and Ericsson cycles are
Reversible cycles
Irreversible cycles
Semi-reversible cycles
Quasi-static cycles
According to Kelvin-Planck's statement, a perpetual motion of the __________ is impossible.
First kind
Second kind
Third kind
None of these
Which is the false statement about true stress strain method?
It does not exist
It is more sensitive to changes in both metallurgical and mechanical conditions
It gives a more accurate picture of the ductility
It can be correlated with stress strain values in other tests like torsion, impact, combined stress tests etc.
The stress induced in a body, when suddenly loaded, is ________ the stress induced when the same load is applied gradually.
Equal to
One-half
Twice
Four times
According to Kelvin-Planck's statement of second law of thermodynamics,
It is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work
It is possible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy into work
It is impossible to construct a device which operates in a cyclic process and produces no effect other than the transfer of heat from a cold body to a hot body
None of the above
Which is the incorrect statement about Carnot cycle?
It is used as the alternate standard of comparison of all heat engines.
All the heat engines are based on Carnot cycle.
It provides concept of maximising work output between the two temperature limits.
All of the above
In a uniform bar, supported at one end in position, the maximum stress under self weight of bar shall occur at the
Middle of bar
Supported end
Bottom end
None of these
Formula based on IS codes is based on
Straight line formula
Eulers formula
Rankines formula
Secant formula
Euler's formula holds good only for
Short columns
Long columns
Both short and long columns
Weak columns
The heat absorbed or rejected by the working substance is given by (where ds = Increase or decrease of entropy, T = Absolute temperature, and dQ = Heat absorbed or rejected)
δQ = T.ds
δQ = T/ds
dQ = ds/T
None of these
A cycle consisting of two isothermal and two isentropic processes, is known as
Carnot cycle
Stirling cycle
Ericsson cycle
Joule cycle
The mass of carbon per kg of flue gas is given by
(11/3) CO2 + (3/7) CO
(3/7) CO2 + (11/3) CO
(7/3) CO2 + (3/11) CO
(3/11) CO2 + (7/3) CO
The ratio of specific heat at constant pressure (cp) and specific heat at constant volume (cv) is always __________ one.
Equal to
Less than
Greater than
None of these
A cube subjected to three mutually perpendicular stress of equal intensity p expenses a volumetric strain
3p/E × (2/m - 1)
3p/E × (2 - m)
3p/E × (1 - 2/m)
E/3p × (2/m - 1)
When wood is heated with a limited supply of air to a temperature not less than 280°C, the resulting fuel is
Coke
Wood charcoal
Bituminous coal
Briquetted coal
The energy stored in a body when strained within elastic limit is known as
Resilience
Proof resilience
Strain energy
Impact energy
In the below figure, the stress corresponding to point D is
Yield point stress
Breaking stress
Ultimate stress
Elastic limit
Elasticity of Mild Steel specimen is defined by
Hookes law
Yield point
Plastic flow
Proof stress