Nuclei · Question 67

A sample of radioactive element containing 4 1016 active nuclei. Half-life of element is 10 days, then number of decayed nuclei after 30 days

1. 0.5 1016
2. 2 1016
3. 3.5 1016
4. 1 1016

X(n, ) 73Li, then X will be

1. 105B
2. 95B
3. 114Be
4. 42He

Mn and Mp represent the mass of neutron and proton respectively. An element having mass M has N neutrons and Z protons, then the correct relation will be

1. M < \N Mn + Z Mp\
2. M > \N Mn + Z Mp\
3. M = \N Mn + Z Mp\
4. M = N\Mn + Mp\

Energy released in nuclear fission is due to

1. some mass is converted into energy
2. total binding energy of fragments is more than the binding energy of parental element
3. total binding energy of fragments is less than the binding energy of parental element
4. total binding energy of fragments is equal to the binding energy of parental element

Which rays contain (positive) charged particles?

1. -rays
2. -rays
3. -rays
4. X-rays

Half life of a radioactive element is 12.5 hours and its quantity is 256 g. After how much time its quantity will remain 1 g?

1. 50 h
2. 100 h
3. 150 h
4. 200 h

Nuclear fission is best explained by

1. liquid drop model
2. Yukawa -meson theory
3. independent particle model of the nucleus
4. proton-proton cycle

For the given reaction, the particle X is 6C11 5B11 + + + X

1. neutron
2. anti neutrino
3. neutrino
4. proton

The relation between and T1/2 is ( T1/2 half-life)

1. T1/2 = 2
2. T1/2 2 =
3. T1/2 = 1
4. ( + T1/2) = 2