CBSE
Multiple Choice QuestionsThe number of -particles and β-particles respectively emitted in the reaction 88A196 → 78B164 are
8 and 8
8 and 6
6 and 8
6 and 6
C14 has half-life 5700 yr. At the end of 11400 yr, the actual amount left is
0.5 of original amount
0.25 of original amount
0.125 of original amount
0.0625 of original amount
The counting rate observed from a radioactive source at t = 0 was 1600 count/s and at t = 8 s it was 100 counts/s. The counting rate observed as counts per second at t = 6 s, will be
400
300
250
200
If M is atomic mass, A is mass number of a nucleus, then is called
mass defect
fermi energy
binding energy
packing fraction
Which of the following is not conserved in nuclear reaction ?
Total energy
Mass number
Charge number
Number of fundamental particles
Li nucleus has three protons and four neutrons. Mass of lithium nucleus is 7.016005 amu. Mass of proton is 1.007277 amu and mass of neutron is 1.008665 amu. Mass defect for lithium nucleus in amu is
0.04048 amu
0.04050 amu
0.04052 amu
0.04055 amu
A radioactive nucleus A finally transforms into a stable nucleus B. Then A and B can be
isobars
isotones
isotopes
none of these
If 92U238 emits 8 -particles and 6 β-particles, then the resulting nucleus is
82U206
82Pb206
82U210
82U214
The half-life of a radio-isotope is 4 h. If initial mass of the isotope was 200 g, then mass remaining after 24 h will be
1.042 g
2.084 g
3.125 g
4.167 g
Which of the following statement is correct ?
The rest mass of a stable nucleus is less than the sum of the rest masses of its separated nucleons.
The rest mass of a stable nucleus is greater than the sum of the rest masses of its separated nucleons.
In nuclear fission, energy is released by fusion two nuclei of medium mass (approximately 1O0 amu).
In nuclear fission, energy is released by fragmentation of a very low nucleus.
