In the X-ray radiography technique, the tube voltage for thicker plates as compared to thin plates, should be
Higher, as it gives higher wavelength
Lower, as it gives higher wavelength
Higher, as it gives shorter wavelength
Lower, as it gives shorter wavelength
Correct Answer :
C. Higher, as it gives shorter wavelength
Related Questions
Resistance of an electrical conductor is proportional to its (where, l = length and A = cross-sectional area of the conductor)
A
l
A2
Both 'a' & 'b'
Flue gases pass through the following boiler accessories in a high pressure natural circulation boiler.
A. Induced draft fan
B. Economiser
C. Air preheater
D. Steam superheater Which of the following gives the correct sequence of flow of the flue gases through the above mentioned boiler accessories?
A, C, B, D
D, B, C, A
D, C, B, A
D, A, B, C
Primary designation of steel is based on its
Hardness & tensile strength
Carbon content
Iron content
Alloying elements content
Brass parts with high residual tensile stress at the surface are susceptible to season cracking (i.e. spontaneous cracking occuring on exposure to atmospheric corrosion), if its zinc percentage is more than
5
10
20
35
To improve the machinability of steel, it is generally subjected to
Spheroidising
Tempering
Normalising
Annealing
For an ideal gas, Cp - Cv is
R
-R
0
(3/2) R
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
If a solid is compressed adiabatically in its elastic range, its __________ remains constant
Internal energy
Enthalpy
Entropy
Temperature
Which of the following performance characteristics of a S.I engine is not affected by the front end volatility of the petrol used?
Vapour locking
Hot starting
Spark plug fouling
All 'a', 'b' & 'c'
The dimensional formula of bulk modulus of elasticity is same as that of the
Pressure
Density
Force
None of these
Brinell Hardness Number (BHN) for talc is approximately in the range of
1-5
20-30
100-150
200-250
A solar cell converts the sunlight directly into __________ energy.
Thermal
Electrical
Mechanical
Chemical
'Ice point' is designated on Fahrenheit temperature scale by
0°
32°
62°
212°
High endurance limit of carburised machine parts is because of the fact that carburisation
Suppresses any stress concentration produced in the parts
Enhances the yield point of the material
Introduces a compressive layer on the surface
Produces a better surface finish
__________ is not used as a material of construction in thermocouples.
Alumel
Rhodium
Constantan
Duralumin
The maximum thickness of the metal which can be welded using ultrasonic welding is __________ mm.
0.5
3
10
25
Atomic __________ is a whole number for an element.
Number
Weight
Radius
None of these
Diffusion co-efficient of a metal in a solid solution depends upon its
Composition
Temperature
Both (A) & (B)
Neither (A) nor (B)
Thermal efficiency of an internal combustion engine is around __________ percent.
8
35
65
80
CANDU type nuclear reactor using natural uranium as fuel is the extensively used nuclear reactor because of the fact that the
Specific fuel consumption is very low due to the use of heavy water
Fuel cost is much lower than that used in pressurised water or boiling water reactor
Heavy water is used both as coolant as well as moderator
Both 'b' & 'c'
Which of the following alloying elements is present in maximum percentage in high speed steel?
Molybdenum
Chromium
Tungsten
Vanadium
Aluminium is extracted from
Chalcocite
Bauxite
Galena
None of these
Wohler test is a destructive test to find out the __________ strength of a prepared metal specimen.
Creep
Fatigue
Endurance
Tensile
Which of the following is the correct nature of shear stress distribution along the cross section in a horizontal circular pipe under steady state fluid flow condition?
Dryness fraction of dry steam is
0
∞
1
0.5
Gross national product (GNP) means the total value of __________ in a country.
Goods produced
Gold reserve
Earning of the citizens
Taxes paid
The most suitable material of construction for a sewer to carry sewage under high pressure is
Asbestos cement
Steel
Cement concrete
Stoneware
Globular form of cementite is formed during the __________ process.
Spheroidising
Hardening
Annealing
Normalising
Uniform ramming of sand in green sand moulding process leads to
Reduced chance of gas porosity
Greater dimensional stability of the casting
Uniform flow of molten metal into the mould cavity
Less sand expansion type of casting defect
Routing in production, planning & control is concerned with the
Sequence of operation to be performed
Progress of work performed
Authorisation of work to be performed
Balancing of load on machines