Chapter 13 physics class 12 explains in detail the following concepts:

Composition of nucleus:

• Protons and neutrons make up the nucleus.
• Protons are positively charged particles found inside the nucleus while neutrons are neutral since they are devoid of charge.

Atomic number:

• The total number of protons in an atom's nucleus is represented by its atomic number.

Mass of an atom:

• The total number of neutrons and protons contained inside the nucleus is referred to as atomic mass.
• Because electrons are the lightest particles, their mass is not taken into account when determining the mass of the atom; only the mass of neutrons and protons (constitute the nucleus) are taken into account.

Measurement of atomic mass unit:

• In comparison to the quantifiable masses we perceive around us, the mass of an atom is extremely tiny.
• The atomic mass unit (a.m.u) is a unit of measurement for the mass of an atom.
• The atomic mass unit is equal to one-twelfth of the mass of carbon.

• As given in chapter 13 physics class 12, a stream of alpha particles was made to travel through a tiny thin gold foil in a Rutherford scattering experiment.
• Only a few alpha particles were deflected.
• Because alpha particles are positively charged (they were divalent helium molecules), they were deflected by repulsion with the nucleus.
• Because they are both positively charged, they repel each other.
• A relatively tiny number of alpha particles were deflected, indicating that the nucleus is rather small.

Mass energy:

• Other types of energy can be converted from mass energy.
• The mass-energy equivalence relation, as defined by Einstein, is: - E=mc2.
• Any item having mass ‘m' has mass energy associated with it, which is denoted by the symbol mc2.
• This relationship aids in the comprehension of nuclear masses and nuclei interactions.

Nuclear binding energy:

• Nuclear binding energy is the amount of energy necessary to keep the protons and neutrons in an atom's nucleus together.
• As a result of the energy required to maintain neutrons and protons together, the nucleus remains intact.
• It may alternatively be described as the amount of energy required to separate the nucleons.
• Nuclear binding energy is a measure of how firmly nucleons are linked to one another.

• The force that holds the nucleons (protons and neutrons) together is known as nuclear force.
• The nucleons are held together by a strong attractive force.
• When compared to other natural forces such as gravitational or coulomb's forces, the nuclear force is the most powerful of them all.
• Protons repel each other because they are positively charged.
• Coulomb's repulsion force is the source of this repulsion force.
• Because the nuclear force is greater than the coulomb's force, it overcomes the repulsion force.
• Inside the nucleus, neutrons and protons are bound together by this force.

• According to the explanation given in chapter 13 physics class 12, radioactivity is a nuclear phenomenon that occurs when an unstable nucleus decays into a stable nucleus.
• Physicist Henry Becquerel discovered radioactivity by accident. The story behind this is given in class 12 physics chapter 13 NCERT solutions.
• The phenomena of radioactivity will only be seen in unstable nuclei.
• Fluorescent products have a feature called fluorescence, which means that when visible light falls on them, they emit light.
• Experimental setup (given with demonstration in class 12 physics chapter 13 NCERT solutions):
• He placed a photographic plate inside a box and a fluorescent item on top of the box and exposed them to the sun.
• The box's opaque nature prevents light rays from passing through.
• There should be no remnants of pictures on the photographic plate after it is processed.
• He repeated the experiment with other chemicals and discovered that no picture was produced on the photographic film.
• This demonstrated that the sole beam released in the aforementioned situation is sunlight, which cannot reach the plate since it is obscured by an opaque object.

• Class 12 physics chapter 13 NCERT solutions explains nuclear energy as the force that binds atom nuclei together.
• Nuclear energy may be created from nuclei by either breaking a heavy nucleus into two lighter nuclei (nuclear fission) or combining two lighter nuclei to generate a heavy nucleus (nuclear fusion).
• Nuclear energy is emerging as a potential answer to the global energy issue.
• Nuclear energy may be used to generate electricity.

A given coin has a mass of 3.0 g. Calculate the nuclear energy that would be required to separate all the neutrons and protons from each other. For simplicity, assume that the coin is made entirely of (2963Cu) atoms (of mass 62.92960 u).

Mass of a copper coin, m’ = 3 g

Atomic mass of (2963Cu) atom, m = 62.92960 u

The total number of (2963Cu) atoms in the coin, N = (NA x m’)/ (Mass number)

Where,

NA = Avogadro’s number = 6.023 × 1023 atoms /g

Mass number = 63 g

Therefore N = (6.023 × 1023 x3)/ (63) =2.868x1022 atoms.

(2963Cu) nucleus has 29 protons and (63-29) = 34 neutrons.

Therefore, Mass defect of this nucleus, ∆m' = 29 × mH + 34 × mn − m

Where,

Mass of a proton, mH = 1.007825 u

Mass of a neutron, mn = 1.008665 u

Therefore, ∆m' = 29 × 1.007825 + 34 × 1.008665 − 62.9296

= 0.591935 u

Mass defect of all the atoms present in the coin, ∆m = 0.591935 × 2.868 × 1022

= 1.69766958x1022u.

But 1 u = 931.5 (MeV/c2)

Therefore, ∆m = 1.69766958 × 1022 × 931.5 (MeV/c2)

Hence, the binding energy of the nuclei of the coin is given as:

Eb = ∆mc2

= 1.69766958 × 1022 × 931.5(MeV/c2)/c2

= 1.581 × 1025 MeV

But 1 MeV = 1.6 × 10−13 J

Eb = 1.581 × 1025 × 1.6 × 10−13

= 2.5296 × 1012 J

This is the energy required to separate all the neutrons and protons from the given coin.

1. What is the nucleus definition?

Class 12 physics chapter 13 NCERT solutions explains that electrically charged protons and electrically neutral neutrons make up atomic nuclei (nucleons). The strongest known basic force, known as the strong force, holds them together. Although the nucleus accounts for less than .01% of the atom's volume, it generally comprises more than 99.9% of the mass.

2. What are the salient aspects of NCERT Solutions for Class 12 Physics Chapter 13 Nuclei?

On its website, you can find NCERT Solutions for Class 12 Physics Chapter 13 Nuclei. Some of the major aspects of MSVgo's NCERT Solutions for Class 12 Physics Chapter 13 include the following:

• Aligned with the most recent curriculum and exam format
• Provides step-by-step instructions
• Compiled by experts in the field
• Can be obtained for free in PDF format
• Completely covers NCERT questions

3. What are the benefits of NCERT Solutions for Class 12 Physics Chapter 13 Nuclei?

Chapter 13 of CBSE Class 12 Physics Nuclei is a crucial chapter in the exams. The NCERT Solutions for Nuclei explains the topics and answers questions about the chapter. To do well on tests, it is critical to be well-versed in this chapter and the Class 12 Physics Chapter 13 NCERT Solutions helps students to do just that as it includes expert responses for students who have questions regarding the complex topics covered. The tutors responsible for curating NCERT Solutions for Nuclei have years of experience teaching the subject. Class 12 NCERT Solutions Chapter 13 Nuclei is an excellent strategy to excel on the Physics test.