Atomic weight of boron is 10.81 and it has two isotopes . THen, the ratio of atoms of in nature would be.
19 : 81
10 : 11
15 : 16
81 : 19
In nuclear fission process, energy is released because.
mass of products is more than mass of element
total binding energy of produces formed due to nuclear fission is more than the parent fissionable material.
total binding energy of products formed due to nuclear fission is less than parent fissionable material.
mass of some particles is converted into energy.
A radioactive sample with a half -- life of 1 month has the lavel : 'Activity = 2 microsrocrie on 1-8-1991'. What would be its activity two months earlier?
1.0 microcurie
0.5 microcurie
4 microcurie
8 microcurie
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.
Solar energy is mainly caused due to.
fision of protons during synthesis of heavier elements
gravitational contraction
burning of hydrogen in the oxygen
fission of uranium present in the sun
A nucleus ruptures into two nuclear parts which have their velocity ratio equal to 2 : 1,. What will be the ratio of their nuclear size.
21/3 : 1
1 : 21/3
31/3 : 1
1 : 31/2
mp and mn are masses of proton and neutron respectively. An element of mass m has Z protons and N neutrons, then.
m > Zmp + Nmn
m = Zmp + Nmn
m < Zmp + Nmn
m may be greater than, less than or equal to m Zmp + Nmn depending on nature of element.
A free neutron decays into a proton, an electron and.
A beta particle
An alpha particle
an antineutrino
a neutrino
The constituents of atomic nuclei are believed to be.
Neutrons and protons
Protons only
Electrons and protons
Electrons, protons and neutrons
The binding energy of deuteron is 2.2 MeV and that of is 28 MeV. If two deuterons are fused to form on , then the energy released is.
25 . 8 MeV
23.6MeV
19 . 2MeV
30. 2 MeV
