Solar energy is due to
fusion reaction
combustion reaction
fission reaction
chemical reaction
A radioactive element has half-life period 800 yr. After 6400 yr what amount will remain?
1/2
1/16
1/8
1/256
Which of the following statements is true for nuclear forces?
They obey the inverse square law of distance.
They obey the inverse third power law of distance.
They are short range forces.
They are equal in strength to electromagnetic forces.
An element A decays into element C by a two step process
Then
A and C are isotopes
A and C are isobars
A and B are isotopes
A and B are isobars
The average binding energy of a nucleon inside an atomic nucleus is about
8 MeV
8 eV
8 J
8 erg
The mass number of He is 4 and that for sulphur is 32. The radius of sulphur nuclei is larger than that of helium by
√8
4
2
8
What is the respective number of α and β particles emitted in the following radioactive decay
200X90 → 168Y80?
6 and 8
6 and 6
8 and 8
8 and 6
The ratio of the radii of the nuclei 13Al27 and 52Te125 is approximately
6 : 10
13 : 52
40 : 177
14 : 73
The stable nucleus that has a radius half that of Fe56 is
Li7
Na21
S16
Ca40
Which of the following is used as a moderator in nuclear reactors?
Plutonium
Cadmium
Heavy water
Uranium
