NEET Physics Nuclei Class 12 Questions

In the nuclear emission stated above, the mass number and atomic number of the product \( Q \) respectively, are:

The half life of a radioactive substance is 20 minutes. In how much time, the activity of substance drops to (1/16)^th of its initial value?

In the given nuclear reaction, the element X is: ₂₃₁Na → X + e⁺ + ν

A nucleus of mass number 189 splits into two nuclei having mass number 125 and 64. The ratio of radius of two daughter nuclei respectively is:

A radioactive nucleus undergoes spontaneous decay in the sequence X → Y → Z → C → D, where Z is the atomic number of element X. The possible decay particles in the sequence are :

The half-life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be :

A nucleus with mass number 240 breaks into two fragments each of mass number 120, the binding energy per nucleon of unfragmented nuclei is 7.6 MeV while that of fragments is 8.5 MeV. The total gain in the Binding Energy in the process is :

Tritium, a radioactive isotope of hydrogen, emits which of the following particles?

The energy equivalent of 0.5 g of a substance is:

The energy required to break one bond in DNA is 10⁻²⁰ J. This value in eV is nearly:

When a uranium isotope ²³⁵U is bombarded with a neutron, it generates ⁹¹Kr, three neutrons and:

α-particles consist of:

For a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is

Radioactive material ‘A’ has decay constant ‘8λ’ and material ‘B’ has decay constant ‘λ’. Initially they have same number of nuclei. After what time, the ratio of number of nuclei of material ‘B’ to that ‘A’ will be 1/e?

When an α-particle of mass m moving with velocity v bombards on heavy nucleus of charge 'Ze', its distance of closest approach from the nucleus depends on m as

If radius of the \( ^{27}_{13}Al \) nucleus is taken to be R_{Al} then the radius of \( ^{125}_{53}Te \) nucleus is nearly

The binding energy per nucleon of ³Li₇ and ⁴He₂ nuclei are 5.60 MeV and 7.06 MeV respectively. In the nuclear reaction ³Li₇ + ¹H → ⁴He₂ + ⁴He₂ + Q, the value of energy Q released is

How does the Binding Energy per nucleon vary with the increase in the number of nucleons?

α-particles, β-particles and γ-rays are all having same energy. Their penetrating power in a given medium in increasing order will be: