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“The Cosmic Engine” Physics Course Essay

Describe how energy can be released from the nuclei of atoms (6) Most nuclei are stable. Consisting of protons and neutrons, they are unaffected by chemical reactions and have remained the same since they were formed. However, some nuclei are unstable and spontaneously release energy in the form of a Helium nucleus (a Alpha),an electron (P Beta) and y Gamma rays. These nuclei are known as radioactive and it’s not possible to predict when a particular radioactive nucleus will emit this energy but a large number of materials are said to have a ‘half life’.

The Alfa life is the time it takes for half the nuclei to emit their radiation. 1 . Describe and compare the nature of emissions from the nuclei of atoms as radiation of alpha a and beta particles and gamma y rays in terms of: (6) Ionizing power Penetrating power Effect of magnetic field Effect of electric Field Alpha Particles: Alpha particles are composed of two protons and two neutrons and have the same nucleus as Helium. It is a very stable particle. Large nuclei such as Americium-241 emit alpha particles.

As it emits alpha particles its mass and atomic number decrease, so it changes into a different element. Alpha particles are good unionizes because of their double positive charge, large mass and because they are relatively slow compared to beta particles. They can also cause multiple nominations within a very small distance. Because alpha particles are highly ionizing, they are unable to penetrate very far through matter and are brought to rest by a few centimeters of air or less than a tenth of a millimeter of living tissue.

After traveling through air for a few centimeters, it will capture electrons and become a Helium atom. Because alpha particles possess the charge of two protons, when they move through a genetic or electric field a force is exerted on them. This force causes them to accelerate and deflect from their original path. Beta Particles: neutron spontaneously decays into a proton and electron, the electron is immediately ejected from the nucleus at a high speed creating the Beta particle. Beta particles are much smaller than alpha particles, being only about 117200th the mass of them.

Beta particles are much less ionizing than alpha particles and generally do less damage for a given amount of energy deposition, but they can penetrate matter further than alpha particles. Where alpha particles can be stopped by a sheet of paper, beta articles can be stopped by a sheet of metal. Negatively charged Beta particles also experience a force when they move through a magnetic or electric field. At the same speed, a Beta particle will experience half the force that an alpha particle does.

The incredibly small mass of beta particles compared to alpha particles means that the force has a greater effect on them and causes a much greater deflection. Their paths bend to a much greater extent than alpha particles. Gamma Rays: Gamma rays are an electromagnetic radiation with a very high frequency and very short wavelength. The rays could be described in terms of a stream of photons, which are measles’s particles each traveling in a wave-like pattern and moving at the speed of light.

Gamma photons are the most energetic photons in the electromagnetic spectrum. They are emitted from the nucleus of an atom and are also associated with the fission and fusion of an atom and can accompany a and decays. Gamma rays have a very high ability to penetrate matter and have a low ability to cause insulation. Gamma rays are not particles and do not possess any electric charge. They are unaffected by electric and magnetic fields, therefore they will move through these fields without deflecting. ICC] I Radiation I What it is I Ionizing ability I Penetrating power I Effect of electric or I magnetic field I I a – Alpha particles I Helium nucleus (two protons I High land two neutrons) Beta particles I Electrons I Low I Moderate I Small deflection Great deflection I High I I y – Gamma particles I Electromagnetic radiation I No deflection 1 . Identify the nature of emissions reaching the Earth from the Sun (4) The emissions that reach the Earth from the Sun are known as the solar wind. The solar wind consists mainly of protons that the sun ejects towards the Earth on an average of km/second.

Electrons and ions make up a small percentage of the solar wind. The sun’s corona (see below) causes particles to move so fast that gravity cannot keep them around the sun. The corona is the source of the solar wind. The Sun’s corona taken by X-ray image 1 . Describe the particulate nature of solar wind (4) The solar wind is made of hot plasma, which consists of ions, protons and electrons. Travels at 400-500 km/h The density of the solar wind is measured in the number of per cubic centimeter.

Although usually between 1-10 protons per cubic centimeter, the density can be many times this when a solar flare is directed awards or strikes the Earth. 1 . Outline the cyclic nature of sunspot activity and its impact on Earth through solar winds (4) Sunspot activity is cyclic and peaks every 1 1 years, with sunspots, flares and coronal mass injections increasing- which disrupt electromagnetic communication and electrical grids, causing massive blackouts and power outages due to power shut down safety protocols in place to counteract any damage from solar flares. 1 .

Describe sunspots as representing regions of strong magnetic activity and lower temperature (4) Sunspots are temporary regions on the surface of the sun that have an intense genetic activity and lower temperature. They appear physically dark and form due magnets, they also have two poles. 1 . Gather and process information and use available evidence to assess the effects sunspot activity on the Earth’s power grid and satellite communications (6) When the charged particles of solar wind enters the region of space influenced by Earth’s magnetic field, they are deflected towards the polar regions as shown below.

Their paths spiral towards the north and south magnetic poles. The flow changes the magnetic field of the Earth on the surface, which in turn can induce voltages in long ire’s such as those used to transmit energy over large distances. Automatic safeguards that protect electricity transmission grids from being overloaded may be triggered, cutting off power supplies to whole regions. Satellite communications may also be directly and indirectly affected by solar flare events.

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