IPA FISIKA : Reaksi Nuklir Fisi dan Fusi (Pembelahan dan Penggabungan Inti Atom)

Summary

The video explains nuclear reactions, distinguishing between fission and fusion. Fission involves splitting heavy atomic nuclei into lighter ones, releasing energy, neutrons, and gamma rays. A chain reaction in uranium can lead to controlled energy release in nuclear reactors or uncontrolled explosions in atomic bombs. Fusion, the process of combining light atomic nuclei, releases energy but requires extremely high temperatures and pressures, like those in the sun. Current fusion reactions can only be sustained in stars, though experimental methods aim to replicate them on Earth using high-energy techniques like inertial confinement and thermonuclear reactors.

Takeaways

• 😀 Physical reactions involve the splitting of heavy atomic nuclei into lighter ones, releasing energy and neutrons.
• 😀 Uranium-235, when bombarded with neutrons, forms Uranium-236, which is unstable and undergoes radioactive decay.
• 😀 Uranium-236 splits into Barium-144 and Krypton-89, releasing 3 neutrons and gamma radiation, initiating a chain reaction.
• 😀 A chain reaction in nuclear fission forms the basis of nuclear reactors and atomic bombs.
• 😀 Nuclear reactors are controlled environments where the chain reaction can be sustained for energy production.
• 😀 If the neutron count becomes uncontrollable, the reaction continues indefinitely, leading to massive energy release, as seen in atomic bombs.
• 😀 Nuclear fusion involves the merging of lighter atomic nuclei to form a heavier one, without a chain reaction.
• 😀 Fusion reactions, like the combination of Deuterium and Tritium to form Helium and release gamma radiation, require high energy to overcome electrical repulsion between the nuclei.
• 😀 Two methods for inducing nuclear fusion: using an accelerator or heating Deuterium and Tritium to 15 million degrees Celsius in a thermonuclear reactor.
• 😀 Currently, sustained fusion reactions only occur in the cores of stars like the Sun, which have the necessary temperature and pressure conditions.

Q & A

What is a physical reaction in nuclear science?

A physical reaction in nuclear science refers to the splitting of a heavy atomic nucleus into two lighter nuclei. This process results in the release of energy and neutrons.

What happens when Uranium-235 is bombarded with neutrons?

When Uranium-235 is bombarded with neutrons, it becomes Uranium-236, which is unstable and undergoes radioactive decay, leading to a chain reaction.

What is a chain reaction in nuclear physics?

A chain reaction occurs when neutrons produced by a nuclear fission reaction trigger the fission of additional Uranium-235 nuclei, leading to a self-sustaining series of reactions.

How is energy produced in nuclear reactors?

Energy in nuclear reactors is produced by controlled chain reactions of nuclear fission. The energy released is harnessed to generate electricity.

What happens if the number of neutrons is uncontrolled in a nuclear reaction?

If the number of neutrons is not controlled, it leads to an uncontrolled chain reaction, which can cause an explosion, such as in an atomic bomb.

What is nuclear fusion?

Nuclear fusion is the process where two light atomic nuclei, like hydrogen isotopes (deuterium and tritium), combine to form a heavier nucleus, releasing a significant amount of energy.

Why is nuclear fusion difficult to achieve on Earth?

Nuclear fusion is difficult to achieve on Earth because the hydrogen isotopes have positive electrical charges and repel each other. It requires extremely high temperatures and pressure to overcome this repulsion.

What are the two methods for achieving nuclear fusion?

The two methods for achieving nuclear fusion are: 1) using an accelerator to accelerate and collide the hydrogen isotopes, and 2) heating deuterium and tritium to 15 million degrees Celsius under high pressure, known as thermonuclear fusion.

How does the Sun facilitate nuclear fusion?

The Sun facilitates nuclear fusion by maintaining extremely high temperatures (around 15 million degrees Celsius) and pressure in its core, which are necessary for the fusion of hydrogen atoms into helium.

What is the current state of nuclear fusion on Earth?

As of now, sustained nuclear fusion has only been achieved in the Sun's core and in experimental fusion reactors, but it has not yet been made viable for long-term energy production on Earth.