mechanical engineering MCQs – Page 51

Practise multiple-choice questions from mechanical engineering for competitive examinations and subject revision. Review each marked answer and report any item that may be outdated or unclear.

2501. The energy required to be applied to a radioactive nucleus for the emission of a neutron is________________?
comments icon0

A. 1 MeV

B. 4.3 MeV

C. 20 MeV

D. 7.8 MeV

E. 2.4 MeV

2502. Which of the following are ferrite materials__________________?
comments icon0

A. U233andPu239

B. U

C. U238andTh239

D. none of the above

E. U238andPu239

2503. Ideally the neutron flux in reactor should be__________________ ?
comments icon0
A. uniform throughout

B. maximum in center and zero at side

C. maximum at side and zero in center

D. zero throughout

E. none of the above

2504. The nuclear power plant at Tarapur has the following reactor________________?
comments icon0

A. pressurised water

B. fast breeder

C. sodium graphite

D. none of the above

E. boiling water
2505. U235 will undergo fission by__________________?
comments icon0
A. either fast or slow neutrons

B. low energy (slow) neutrons alone

C. high energy (fast) neutrons alone

D. none of the above

E. medium energy neutrons

2506. Half life of a radioactive isotope corresponds to the time required for half of the following to decay__________________?
comments icon0

A. protons

B. electrons

C. neutrons

D. nulceus

E. atom
2507. A fission chain reaction in uranium can be developed by________________?
comments icon0

A. using moderator

B. absorbing all neutrons

C. slowing down fast neutrons so that Uz fission continues by slow motion neutrons

D. accelerating fast neutrons

E. enriching U235

2508. Plutonium is produced________________?
comments icon0
A. by neutron irradiation of Uz

B. in high capacity furnace

C. as basic raw material

D. by neutron irradiation of throium

E. artificially

2509. A fast breeder reactor uses following as fuel_________________?
comments icon0

A. natrual uranium

B. enriched uranium

C. U235

D. plutonium

E. thorium

2510. Uranium-233 is produced__________________?
comments icon0

A. by neutron irradiation of Uz

B. by neutron irradiation of thorium

C. as basic raw material

D. in high capacity furnaces

E. artificially

2511. In order to have constant clain reaction to produce a constant rate of heat output, the value of ratio of the number of neutrons in one generation to the number of neutrons in the immediately preceding generation must be________________?
comments icon0

A. less than 1.0

B. greater than 1.0

C. equal to zero

D. equal to 1.0

E. equal to infinity

2512. A fast breeder reactor__________________?
comments icon0

A. uses graphite rods as moderator

B. uses ferrite material as moderator

C. has no moderator

D. has powerful moderator

E. uses pressurised water as moderator

2513. In triggering fission, the following types of neutrons are desirable_________________?
comments icon0

A. fast moving

B. neutrons at rest

C. slow moving

D. critical neutrons

E. none of the above

2514. The presence of reflector in nuclear power plants results in___________________?
comments icon0

A. increased production of neutrons

B. controlled production of neutrons

C. complete absorption of neutrons

D. decrease of speed of neutrons

E. decreased leakage of neutrons
2515. The risk of radioactive hazard is greatest in the turbine with following reactor___________________?
comments icon0

A. all of the above.

B. boiling water

C. liquid metal cooled

D. gas cooled

E. pressurised water

2516. Which of the following can be used as a coolant in nuclear plant________________?
comments icon0
A. light or heavy water

B. carbon tetrachloride

C. freon

D. carbon dioxide

E. molten lead

2517. In the breeder reactors the generation of new fissionable atom is_________________?
comments icon0
A. at a higher rate than the constuption

B. unpredictable

C. at the lower rate than the consumption

D. depends on other considerations

E. at an equal rate of the consumption

2518. The function of control rods in nuclear plants is to__________________?
comments icon0

A. control absorption of neutron

B. readioactive pollution

C. none of the above

D. control temperature

E. control fuel consumption

2519. The fuel needed, with reflector in nuclear power plant, in order to generate sufficient neutrons to sustain a chain reaction, would be________________?
comments icon0
A. less

B. zero

C. more

D. same

E. negative, i.e. fuel would be generated

2520. Supertheated steam is generated in following reactor________________?
comments icon0

A. all of the above

B. gas cooled

C. boiling water

D. pressurised water

E. none of the above

2521. Which of the following is secondary fuel ?
comments icon0

A. non oh these

B. U233andPu238

C. U233andPu239

D. Th232andU238

2522. Pick up the wrong statement Fast breeder reactors__________________?
comments icon0

A. are unmoderated

B. are liquid-metal cooled

C. produce more fuel than they consume

D. use water as coolant

E. operate at extremely high power densities.

2523. Enriched uranium may contain fissionable contents of the order of__________________?
comments icon0

A. 1-90%.

B. 1-50%

C. 1-75%

D. 1-25%

E. 1-99%
2524. In a fission process, maximum %age of energy is released as___________________?
comments icon0

A. gradual readioactive decay of fission products

B. kinetic energy of neutrons

C. none of the above

D. instantaneous release of gamma rays

E. kinetic energy of fission products
2525. Which of the following is more appropriate for a moderator. One which_________________?
comments icon0

A. absorbs neutrons

B. regenerates neutrons

C. does not absorb neutrons

D. accelerates neutrons

E. eats up neutrons

2526. Breeder reactors employ liquid metal coolant because it_______________?
comments icon0

A. produces maximum steam

B. breeds neutrons

C. transfers heat from core at a fast rate

D. acts as good moderator

E. increases rate of reaction in core

2527. Solid- fuel for nuclear reactions may be fabricated into various small shapes such as___________________?
comments icon0
A. any one of the above

B. plates

C. pins

D. none of the above

E. pallets

2528. The size of the reactor is said to be critical when_________________?
comments icon0
A. chain reaction can be initiated

B. it produces no power

C. it explodes

D. it produces tremendous power

E. it becomes uncontrollable

2529. Each fission of U235 produces following number of fast neutrons per fission________________?
comments icon0

A. 1 neutrons

B. infinite

C. 2 neutrons

D. 1 neutron

E. 1 2 neutrons

2530. In triggering fission, which type of neutrons are more effective_________________?
comments icon0

A. activated

B. static

C. in bulk

D. slow

E. fast

2531. The coolant used in boiling water reactor is________________?
comments icon0

A. Co2

B. mixture of water and steam

C. liquid metal

D. mercury

E. pressurised water

2532. The most practical fuel for a thermo-nuclear reactor, both from econocical and nuclear consideration is____________________?
comments icon0

A. thorium

B. lithium

C. deuterium

D. uranium

E. plutonium

2533. Which of the following type of pump is used in liquid metal cooled reactor for circulation of liquid metal_________________?
comments icon0

A. reciprocation

B. axial

C. electromagnetic

D. diaphragm

E. centrifugal

2534. The energy produced by a thermal reactor of same size as a breeder reactor is__________________?
comments icon0

A. much more.

B. slightly less

C. almost same

D. slightly more

E. much less
2535. A fast breeder reactor uses_______________?
comments icon0

A. U-239

B. Pu-239

C. U-238

D. 90% U-235

E. U-235

2536. Which of the following is the primary fuel________________?
comments icon0
A. U

B. U238

C. Pu

D. Pu:

E. Ulii

2537. The unit of radio-activity is_____________?
comments icon0
A. curie

B. electron-ampere

C. AMU

D. electron-volt

E. MeV

2538. A boiling water reactor uses following as fuel________________?
comments icon0

A. plutonium

B. thorium

C. enriched uranium

D. natural uranium.

E. U

2539. Reactors for propulsion applications use_________________?
comments icon0

A. natural uranium

B. molten lead

C. thorium

D. any form of uranium

E. plutonium

2540. Reactors designed for propulsion applications are designed for_______________?
comments icon0
A. enriched uranium

B. pure uranium

C. none of the above

D. natural uranium

E. any type of uranium

2541. Pressurised water reactor is designed________________?
comments icon0
A. to prevent the water coolant from boiling in the core

B. to use intermediate coolant

C. for boiling pi water in the core

D. to eliminate the coolant loop of the pressurised water

E. to use liquid sodium metal as coolant

2542. Pick up the wrong statement?
comments icon0

A. In a heterogeneous or solid-fuel reactor, the fuel is mixed in a regular pattern within moderator.

B. Most serious drawback in using water as coolant in nuclear plants is its high vapour pressure

C. Slow or thermal neutrons have energy of the order or 0.025 eV

D. Fast neutrons have energies above 1000 eV

E. Fast reactor uses moderator
2543. Effective moderators are those materials which contain____________________?
comments icon0

A. heavy weight atoms

B. there is no such criterion

C. zero weight atoms

D. critical atoms

E. light weight atoms
2544. The following present serious difficulty in designing reactor shield_________________?
comments icon0

A. alpha particles

B. beta particles

C. thermal neutrons

D. fast neutrons and gamma rays

E. none of the above

2545. A pressurised water reactor employs pressuriser for the following application________________?
comments icon0

A. to Supply high pressure steam

B. to increase pressure of water in primary circut

C. all of the above

D. to maintain constant pressure in primary circuit under varying load

E. to provide subcooled water at high pressure

2546. When a reactor becomes critical, then the production of neutrons is_________________?
comments icon0

A. zero

B. stopped

C. initiated

D. exactly balanced by the loss of neutrons through leakage

E. infinite

2547. In nuclear fission___________________?
comments icon0
A. the original elements change into completely different elements

B. none of the above

C. the molecules rearrange themselves to form other molecules

D. strong>. the electrons of the element change

2548. Plutonium-239 is produced__________________?
comments icon0
A. by neutron irradiation of IT*

B. by neutron irradiation of thorium

C. as basic raw material

D. in high capacity furnaces

E. artificially

2549. The efficiency of a nuclear power plant in comparison to conventional and nuclear consideration is__________________?
comments icon0
A. lower temperature and pressure condi-tions

B. nuclear hazard risk

C. high initial cost

D. higher cost of nuclear fuel

E. high heat rejection in condenser

2550. Artificial radioactive isotopes find application in________________?
comments icon0

A. nuclear fusion

B. nuclear fission

C. medical field

D. nucleonic devices

E. power generation