CBSE
In radioactive decay process, the negatively charged emitted beta particles are:
the electrons present inside the nucleus
the electrons produced as a result of the decay of neutrons inside the nucleus
the electrons produced as a result of collisions between atoms
the electrons produced as a result of collisions between atoms
Monochromatic light of frequency 6.0 x 1014 Hz is produced by a laser. The power emitted is 2 x 10-3 W The number of photons emitted, on the average, by the source per second is:
5 x 1015
5 x 106
5 x 1017
5 x 1017
If the nucleus has a nuclear radius of about 3.6 fm, then would have its radius approximately as:
6.0 fm
9.6 fm
12.0 fm
12.0 fm
If M (A, Z), MP and Mn denote the masses of the nucleus proton and neutron respectively in units of u (1 u = 931.5 MeV/c2) and BE represents its binding energy in MeV, then
M (A,Z) = ZMp + (A-Z)Mn - BE/c2
M (A,Z) = ZMp + (A-Z)Mn + BE
M (A,Z) = ZMp + (A-Z)Mn - BF
M (A,Z) = ZMp + (A-Z)Mn - BF
Two radioactive substance A and B have decay constants 5λ and λ respectively. At t = 0 they have the same number of nuclei. The ratio of a number of nuclei of A to those of B will be after a time interval:
1/ 4λ
4λ
2λ
1/2λ
A nucleus has mass represented by M (A, Z). If Mp and Mn denote the mass of proton and neutron respectively and BE the binding energy (in MeV), then:
BE = [M(A,Z)-ZMp - (A-Z)Mn]c2
BE = [ZMp + (A-Z)Mn -M(A,Z)]c2
BE = [ZMp + AMn - M (A,Z)]c2
BE = [ZMp + AMn - M (A,Z)]c2
Two radioactive materials X1 and X2 have decay constant 5 λ respectively. If initially, they have the same number of nuclei, then the ratio of the number of nuclei of X1 to that of X2 will be 1/e after a time
λ
λ/2
1/4λ
1/4λ
The number of beta particles emitted by radioactive substance is twice the number of alpha particle emitted by it. The resulting daughter is an
isobar of parent
isomer of parent
isotone of parent
isotone of parent
Two nuclei have their mass number in the ratio of 1:3. The ratio of their nuclear densities would be
1:3
3:1
(3)1/3 : 1
(3)1/3 : 1
The binding energy of deuteron is 2.2 MeV and that of is 28 MeV. If two deuterons are fused to form one then the energy released is
25.8 MeV
23.6 MeV
19.2 MeV
19.2 MeV