Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________ kJ.
+4000
-4000
10000
-10000
Correct Answer :
A. +4000
Related Questions
Production of one ton of paper in Indian paper industry consumes about __________ kWh of electricity.
300
800
1400
2000
The size of the tetrahedral void in the closest packing of atoms is __________ that of the octahedral void.
Equal to
Greater than
Less than
Either (A), (B) or (C); depends on the size of atom
Melting point & boiling points of liquid oxygen are respectively - 218.8°C & - 183°C, while the same for liquid nitrogen is - 210°C & - 195.8°C respectively. The difference in melting points of liquid oxygen & liquid nitrogen is not equal to 8.8
°C
°F
°K
°R
Recrystallisation temperature of steel is __________ °C.
50
300
500
800
The function of neutral flux used in the pyrometallurgy of metal extraction is to increase the __________ of the slag.
Fluidity
Basicity
Acidity
Viscosity
The softness or hardness of a grinding wheel depends upon the type & amount of bonding material used. For general purpose cutter grinding __________ grinding wheel is normally used.
Hard
Soft
Silicon carbide
Aluminium oxide
__________ stress cannot be sustained by a fluid in equilibrium.
Shear
Tensile
Compressive
None of these
Which one of the following is incombustible?
H2
CCl4
C2H2
S
A material in which the atoms are arranged regularly in some directions but not in others, is termed as 'mesomorphous material'; an example of which is
Lead
Glass
Mica
Silver
In case of simple harmonic motion, displacement is proportional to the
Velocity
Acceleration
Both (A) & (B)
Neither (A) nor (B)
Working of linear variable differential transducer (LVDT) is based on the principle of variable
Capacitance
Resistance
Mutual inductance
None of these
Increase in the entropy of a system represents the
Degradation of energy
Decrease in system pressure
Increase in the availability of energy
Increase in the temperature
The 'laughing gas' is
Nitrous oxide
Nitric oxide
Nitrogen trioxide
Nitrogen pentoxide
Which of the following properties of a solid is not dependent on crystal imperfection?
Ductility
Semi-conductivity
Melting point
Yield stress
The process of removal of scale formed during hot rolling of steel is termed as
Descaling
Shot blasting
Pickling
Skimming
The malleability of a material is the property by virtue of which it can be rolled or hammered into thin sheets. Which of the following materials has the maximum malleability?
Lead
Copper
Aluminium
Wrought iron
Wave length of X-rays is about 1 angstrom; however it cannot pass through a sheet of
Paper
Cloth
Lead
Aluminium
Which of the following represents the correct time-temperature curve when a block of metal is heated above room temperature & then left to cool in the room following Newton's law of cooling in which the rate of temperature drop will go on decreasing with the passage of time.
The cathode in an electrochemical cell always carries
Negative charge
Positive charge
Zero charge
Positive or negative charge depending upon the nature of the cell
A semi-conductor is damaged & behaves like a conductor, on passing a strong electric current through it, because it heats up the crystals & breaks the covalent bonds resulting in __________ electrons.
Lack of free
Excess of
Decrease in
None of these
Evaporative cooling process employs a combination of cooling and humidification in which the
Sensible heat is added
Sensible heat is removed and the latent heat is added
Latent heat is removed
Sensible heat is added and latent heat is removed
The refrigerant freon-12 is chemically
CCl2F2
CCl3F
CClF3
CCl4F
During sensible cooling of air, its wet bulb temperature
Decreases but dew point remains constant
Increases but dew point remains constant
Increases & the dew point decreases
Decreases & the dew point increases
Which of the following has the highest modulus of elasticity (about 7 × 106 kg/cm2)?
High speed steel
Stainless steel
Tungsten carbide
Superalloys
__________ property of steel increases by addition of large amount of silicon in it.
Mechanical
Machining
Magnetic
Refractory
Out of the following the refractive index is the highest for
Glass
Diamond
Brine
Kerosene
'Amortization' in respect of financial obligation of a company means the
Liquidation of financial obligations on instalment basis
Commitment of financial obligation on priority
Liquidation of all the obsolete equipments of the company
Modernisation of the plant equipments
One ton of refrigeration is not equivalent to the heat removal rate of
200 BTU/minute
50 kcal/minute
50 kJ/sec
3.5 KW
In TIG welding, thoriated tungsten electrodes are used, because it
Has higher current carrying capacity
Has better electron emissivity
Is stronger than ordinary tungsten
Is easy to prepare
Blasting of tri-nitro-toluene (TNT) is done by mixing it with ammonium
Nitrate
Sulphate
Carbonate
Chloride