1 Physics -- Radioactivity and Nuclear Reaction

Differentiate between radioactive decay and nuclear fission.

1 Answers

1. Radioactive Decay:

- Definition: Radioactive decay is a spontaneous process in which an unstable atomic nucleus undergoes a change, resulting in the emission of radiation.

- Mechanism: It occurs when an atomic nucleus is unstable due to an imbalance between the number of protons and neutrons in the nucleus. The unstable nucleus transforms itself into a more stable configuration by emitting radiation.

- Energy Release: In radioactive decay, energy is released in the form of various types of radiation, such as alpha particles, beta particles, or gamma rays.

- Chain Reaction: Radioactive decay is not a chain reaction process, as it happens independently in each unstable nucleus.

2. Nuclear Fission:

- Definition: Nuclear fission is a process where the nucleus of an atom is split into two or more smaller nuclei, accompanied by the release of a large amount of energy.

- Mechanism: It typically occurs when a heavy atomic nucleus, such as uranium-235 or plutonium-239, absorbs a neutron and becomes highly unstable. The nucleus then splits into two or more smaller nuclei, known as fission fragments, and additional neutrons are released.

- Energy Release: Nuclear fission releases an enormous amount of energy in the form of kinetic energy of the fission fragments and additional neutrons. This energy is typically harnessed for various applications, such as electricity generation in nuclear power plants.

- Chain Reaction: Nuclear fission can sustain a chain reaction under certain conditions. When the released neutrons go on to induce fission in other nuclei, and those fission reactions release more neutrons, a self-sustaining chain reaction occurs. This chain reaction can be controlled in nuclear reactors or can be uncontrolled in nuclear weapons.

Protons and neutrons exist together in an extremely small space within the nucleus. How is this possible when protons repel each other?

Firstly you have to get a rough idea of four fundamental forces of nature.

There are four fundamental forces in nature.

1.Gravity.

2.The weak nuclear force.

3.Electromagnetism.

4.The strong nuclear force.

The list is in ascending order in terms of strength.

Proton repelling each other is due electro magnetic force but protons and neutrons sticking to each other is due to strong nuclear force. As strong nuclear force is greater than electro magnetic force, the nucleus has protons and neutrons...

The electron emitted in beta radiation originates from

From the nucleus of an atom

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Heavy unstable nuclei usually decay alpha and beta particle. Why do they not usually emit single proton or neutron?

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Radioactivity is a spontaneous phenomenon. Explain .

Radioactivity is a spontaneous phenomenon because certain atomic nuclei, known as radioactive isotopes, are inherently unstable. They have an imbalance of protons and neutrons, which leads to their instability. In order to achieve a more stable state, these nuclei undergo radioactive decay, emitting radiation in the process. This decay can occur in three main ways: alpha decay, beta decay, and gamma decay. The decay process is not influenced or controlled by external factors but happens...

Define Roentgen , red and rem .

1. Roentgen (R): The Roentgen is a unit measuring the amount of X-rays or gamma rays in the air.

2. Red (Radiation Equivalent Dose): The Red measures the biological effect of radiation on tissues or organs.

3. Rem (Roentgen Equivalent Man): The Rem is an older unit quantifying the radiation dose's potential harm to humans.

Make a comparison of three particles emitted by a radioactive source.

1. Alpha Particles:

- Charge: +2 (double positive charge)

- Mass: 4 atomic mass units (AMU)

- Symbol: α

- Composition: Consists of two protons and two neutrons, similar to a helium nucleus.

- Speed: Moves at a slower speed compared to beta particles and gamma rays.

- Penetration: Due to their larger size and double positive charge, alpha particles have low penetration power. They can be stopped by a few centimeters of air or a sheet of paper.

- Ionization: Alpha particles cause significant...

Draw a graph showing the variation of decay rate with number of active nuclei .

How does a daughter nucleus differ from it's parent nucleus when it emits I)alpha particle ii)beta particle

I) Alpha Decay:

When a nucleus emits an alpha particle, the daughter nucleus has an atomic number that is reduced by 2 compared to the parent nucleus. This means the daughter nucleus is a different element from the parent nucleus.

II) Beta Decay:

a) Beta-Minus Decay (β-): The daughter nucleus has one more proton and one less neutron compared to the parent nucleus. This increases the atomic number of the daughter nucleus by 1 while keeping the mass number the same.

b) Beta-Plus Decay (β+): The...

What is the Higgs boson in simple terms?

The Higgs boson is a particle that helps give mass to other particles in the universe. Its discovery confirmed the existence of the Higgs field, an invisible field that interacts with particles and gives them their mass.

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