CBSE
Multiple Choice QuestionsS32 absorbs energy and decays into which element after two -emissions?
Carbon
Aluminium
Oxygen
magnesium
Assertion: For nuclear reactor, it is desirable to have k = 1.
Reason: Sustained chain reaction occur at this critical condition.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
The nucleus emits one particle and 2β- particles. The resulting nucleus is
Assertion: Mass defect in nuclear reactions is less than 1%.
Reason: In nuclear reaction change in BE/N is generally less than 1%.
If both assertion and reason are true and reason is correct explanation of asertion.
If both assertion and reason are true and reason is not correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
The ratio of the masses of the elements having their nuclear radii 2 fermi and 1 fermi
8
2
3
4
Assertion: More energy is released in fusion than fission.
Reason: More number of nucleons take part in fission.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Asserion: γ-radiation emission occurs after decay.
Reason: Energy levels occurs in nucleus.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
For a nuclear reactor to run in critical condition the reproduction factor k should be
= 1
> 1
< 1
>>> 1
A proton travels few distance in an electric field, then it enters a crossed magnetic field of 1 T and radius 0.2 m, find the velocity of proton
0.2 × 108 m s-1
0.2 × 107 m s-1
0.2 × 106 m s-1
2 × 107 m s-1
Among the following which is used to control the rate of reaction of nuclear fissions reactions?
Water
Heavy water
Cadmium
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