15501. __________ number is sometimes used in place of Grashoff number in free convection heat transfer.
15502. Wrought iron does not have the
15503. Nitriding of steel is a process for
15504. The maximum percentage of chromium that can be added to steel is about
15505. Holes in a plate for rivetted joints is preferably made by
15506. The temperature at which a gas, when subjected to Joule-Thomson expansion, neither cools or heats up, is termed as the __________ temperature. Above this temperature the gas heats up on throttling and below this the gas cools down.
15507. Source of heat supply in a cupola is
15508. Machine tool bodies are usually made of
15509. Out of the following, the best material capable of withstanding shock & vibration without the danger of cracking is
15510. On increasing the yield strength of a steel from 450 to 650 MPa, its __________ will increase.
15511. The refractory brick which has good thermal shock resistance at high temperature but cracks on cooling below 400°C is
15512. The path and movements followed by men, materials & equipments in executing the activities is indicated by the
15513. No cutting fluid is normally used, while machining
15514. An orthotropic material is a special class of anisotropic material, which is described by their properties in three perpendicular directions. An example of orthotropic material is
15515. pH value of rain water in India ranges from
15516. The capital & running costs of similar machines having unequal service life can be compared by the __________ method.
15517. Pick the odd man out.
15518. Maraging steels derive their strength from the following mechanism:
15519. Ceramic compounds as compared to metallic compounds
15520. Pressure exerted by a liquid depends upon its
15521. The most detrimental impurity in high pressure boiler feed water is
15522. Who is the author of the book”Origin of Life”?
15523. The refractory lining of the bottom in a basic electric arc furnace is made of
15524. Alcohols are not suitable as diesel engine fuel because the cetane number of alcohols is
15525. Matte smelting is used in the extraction of
15526. Percentage of differential pressure lost in a venturimeter with a tapering of 15° may be about
15527. Compressed dry air is used as the cutting fluid, while machining
15528. Oxide layer formed on the non-ferrous metal surface after its annealing is
15529. Silicon percentage in silicon steel used for electrical equipments is about
15530. Catalyst used in the 'catalytic converter' employed in automobile exhaust line for complete combustion/oxidation of carbon monoxide, nitrogen oxides and hydrocarbons is
15531. Liquid nitrogen containers can be made from
15532. Materials having __________ lattice structure are usually the most ductile.
15533. Metal cutting by oxy-acetylene flame is accomplished by the __________ of the metal.
15534. The material used for coating the welding electrode is termed as the
15535. In an amorphous material, atoms defy any definite atomic structure and exist in random pattern just like in liquid. Which of the following is an amorphous material ?
15536. Even though heat transfer co-efficients in boiling liquids is large, use of fins is advantageous, when the entire surface is exposed to __________ boiling.
15537. In Newton's law of viscosity, which states that the shear stress is proportional to the __________ Co-efficient of viscosity is called dynamic or absolute viscosity(where, V = velocity, Vg = velocity gradient ).
15538. Which of the following materials has the least scrap value ?
15539. Force between the molecules of the same substance is called __________ force.
15540. Stresses encountered in the metal forming processes are less than the __________ of the material.
15541. Which of the following is not a ferromagnetic material ?
15542. Rain drops falling through atmospheric air attain limited terminal velocity, because of
15543. Addition of silicon to cast iron
15544. Lead is poured into the joint between two __________ pipes.
15545. About __________ ton of coke is required in a cupola to produce one ton of casting.
15546. There are one octahedral void and __________ tetrahedral void in the closest packing of atoms.
15547. Which of the following is prone to cup and cone fracture ?
15548. __________ remains constant during the adiabatic cooling of moist air.
15549. __________ joint is usually used for joining cast iron pipes mostly used for temporary pipelines, where it may be necessary to dismantle & reassemble the pipeline very frequently.
15550. Out of the following, the alloy which has equal percentage of constituents, is