CBSE
Multiple Choice QuestionsIn nuclear fission, which of the following quantity is conserved?
Energy
Mass
Momentum
Both energy and mass
Assertion: is a source of gamma radiation.
Reason: Gamma emission is due to nuclear decay.
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.
Gamma decay takes place
Prior to alpha decay.
Prior to beta decay.
Prior to positron decay.
Due to de-excitment of nuclear levels.
Assertion: Static crashes are heard on radio, when lightning flash occurs in the sky.
Reason: Electromagnetic waves having frequency of radio wave range interfere with radio waves.
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.
Which of the following statement is incorrect?
Neutron is less stable than proton
Neutron can cause fission in nuclear reactors but proton can not.
A free proton can emit beta particle.
A bound proton can emit beta particle.
Electric field at a distance r from infinitely long conducting sheet is proportional to
r-1
r-2
r-3/2
independent of r
When a slow neutron is captured by a nucleus, a fission energy releasing 200 MeV. If power of nuclear reactor is 100 W then rate of nuclear fission is
3.6 × 106 s-1
3.1 × 1012 s-1
1.8 × 104 s-1
4.1 × 106 s-1
Assertion: γ-radiation emission occurs after decay.
Reason: Energy levels occur 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.
In beta plus decay
antineutrino is produced with electron
neutrino is produced with positron
neutron is produced with electron
none of these
Half life of a radio-active element is 8 years, how much amount will be present after 32 years?
