The radioactive decay rate of a radioactive element is found to be 103 disintegrations/second at a certain time. If the half-life of the element is one second the decay rate after one second is
A.103/
B.103/2
C.2 x 103
D.103/2
Category: Nuclear Engineering Mcqs
The half-life period may be best determined by
A.nothing the weight loss over a period of time
B.measuring the volume of helium liberated
C.by counting the number of alpha particles emitted per second in a Geiger Muller Counter from a known amount
D.Calculations based upon the chemical equation for the radioactive disintegration
Select the false statement
A.A definite fraction of a radioactive substance disintegrates in a definite time
B.The half-life time is independent of initial concentration of substance
C.Radioactive disintegration constant is independent of temperature
D.If the half-life time is 1580 years the complete disintegration will take place in 3160 years.
The large energy released in atomic bomb explosion is due to
A.release of neutrons
B.conversion of heavy atoms to lighter atoms
C.appreciable mass loss
D.higher mass of products than initial substance
The life of a meson is about
A.10-18 sec
B.10-2 sec
C.10-18 sec
D.1 sec
In nuclear reactions
A.only the mass number is conserved
B.only the atomic number is conserved
C.the mass number and the atomic number both are conserved
D.neither the atomic number nor the mass number is conserved
Which of the following statements is wrong for deuterium and tritium?
A.Both have same number of protons
B.Both have same number of electrons
C.Both have same number of neutrons
D.Both form neutral exides
The ratio of the mass of an electron to the mass of a proton is
A.1837
B.1/1837
C.183.7
D.1/183.7
An atom can be considered as having a dense nucleus of neutrons and protons and a surrounding distribution of electrons. If there are x neutrons y protons and z electrons what sort of relationship exists between x y and z in a small neutral atom? Where ? means approximately equals.
A.x = y ? z
B.x ? y = z
C.x = y = z
D.x = y-1 = z
Nuclear fission was first experimentally observed by
A.Fermi
B.Rutherford
C.Planck
D.Hahn and strassman
