#### Theories of the Universe

Theories of the Universe There are many theories on the topic of 'everything', but as physicists are simple folk they can only settle for one simple answer. Just one. Most theoretical physicists have believed that, ultimately, there must be just one possible universe, the physical manifestation of a set of laws so compelling that no other option would be viable. One universe. One theory. One defining way. It was a lovely idea, but increasingly it seems a fantasy. In recent years, theory and experiment are leading to the conclusion that, far from being the only option, our universe may be just one among an almost infinite array of possible worlds. It may be that ours is simply one member of a vast cosmological swarm. Several paths seem to be leading in this direction. The most notable is string theory, which is the leading contender for a so-called theory of everything. Many physicists are convinced that some version of string theory will prove to be the final description of all physical reality, unification under one mathematical umbrella of matter, force, space and time. As the name so charmingly implies, string theory proposes that, at its core, the universe is composed of minute strings. To get a sense of what this means, imagine a subatomic particle as a tiny point; now further imagine that, as you look closer, this point turns out to be a tiny closed loop, not a

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#### Wavelength of red light

Quality of Measurement Coursework Wavelength of red light The Aim The target is to take measurements to calculate the wavelength of red laser light by using the diffraction grating formula. Therefore I will use a variety of diffraction gratings. To improve accuracy I will always do the experiment with and in absence of two lenses. With this step I hope to get closer to the real wavelength. The Set-up Equipment list: . red laser 2. two metre rulers 3. wall or projector screen 4. double slit 5. slit holder 6. variety of diffraction gratings 7. diverging lens 8. converging lens 9. two lens holders 0. graph paper 1. cello tape, blue tack 2. marker pens The light from the laser passes through the diverging lens and splits up. Afterwards the converging lens concentrates the light. This process gives a more focused and smaller dot on the wall which leads to higher accuracy. The grating causes the concentrated light to break up again. Maxima occur on the screen where the light is in phase. The dot in the centre is called central maximum or 0th order spectrum. The next dots left and right from the central maximum are called 1st order spectrum; the next ones are called 2nd order spectrum and so on. The measurements . Set up the equipment 2. Cut the graph paper into 4 stripes and glue them together to get one long stripe 3. Stick the long stripe with blue tack on

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#### The Electro magnetic spectrum.

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#### Wave Coursework

Physics Coursework Plan Investigating how the velocity of water waves depends on the depth of water Background knowledge Speed (V/ms-¹) = distance (D/m) ÷ time (T/s) Using this equation I can calculate the speed at which the water wave travels at. The deeper the water, the faster the water wave travels Aim I am going to investigate how the velocity of water waves varies on the depth of the water and will find the relationship between these two variables. Prediction/Hypothesis I believe that when the depth of the water is increases the velocity of the water waves will increase in proportion. Average speed = distance ÷ time Apparatus * Tray * Support stand * Stop watch * Ruler * Water Diagram Variables and constants The only variables of this experiment are to be: * The depth of the water * The velocity of the waves The quantites which will remain constant are: * The temperature of the liquid * The type of liquid * The height at which the tray is lowered from * The number of waves recorded * The same tray is used To ensure a fair experiment, I will record my results 3 times. This will also increase the reliabilty of my results. I will then be able to work out an average, removing any error results out of limit. Before taking any readings of the wave velocity I will measure the length and width of the tray and also see if the tray is flat on the

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#### What affects the voltage output of a solar panel?

What affects the voltage output of a solar panel? Planning Aim The aim of the investigation is to find out how the distance between a light point source and a photovoltaic cell affects the output potential difference. Hypothesis I predict that the further the distance, the smaller the output potential distance Inverse square law for light intensity (Taken from the website - http://hyperphysics.phy-astr.gsu.edu/hbase/vision/isql.html#c1) "Inverse square law for light intensity against distance: As the distance between an observer and a light source increases, the observable brightness decreases with d-2. Light spreads out over an increasing area of space to decrease apparent brightness. (Figure 1.1) Figure 1.1 (http://www.astrosociety.org/education/publications/tnl/32/images/fig5.gif) Because, Pin is proportional to area-1 and area is proportional to distance2, therefore Pin is proportional to distance-2 (figure 1.2). This supports my prediction that the output potential difference will be much smaller when the distance between the point source and the PV cell increases. Of course, my hypothesis assumes 100% efficiency and no influence from background light and other factors that may affect the experiment in anyway. .2 Prediction of outcome (Pin ? distance-2) Apparatus list The list of apparatus to be used is: Ray box Used as the point source to emit light

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#### Astronomy - the urge to explore space.

Astronomy Astronomy has been a very interesting subject for every generation of mankind. From ancient Greeks to the modern astronomers, everyone has tried to explore the space probably due to the urge to discover space and find everything. The urge to explore space did not start lately but this has been passed on from generations of human beings. Some civilisations expressed the deep beauty and the attraction of the shining stars and their constellations in the space above them by worshipping them; whilst others made buildings based upon constellations of stars. A few ancient buildings in the deep and dense tropical forests that have been observed by archaeologists recently caught an astronomer's eye as something other than just an old building. He noticed that the way the building was designed exactly identical to a constellation present in the sky. When studied in detail, it was discovered that the building's door and the main door were exactly the same distance as two stars of the constellation from each other when they were looked at from the naked eye. It was also found out that the building door and the main door were at an angle of 20°. Astonishingly, this is the exact angle that the same two stars of the constellation had on each other. Until the 11th century the truth about the stars was unknown and there were just a few theories of Ancient Greeks. In the 11th

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#### Black Holes Research and Report

Contents Page number 3 What is a Black Hole? Black Hole anatomy 4 Types of Black Hole 5 Event horizon radius 6 Mass of a black hole 7 Hawking radiation 8 What happens when Black Holes Collide? Gravitational lensing 10 Einstein rings Evaluation 11 References Black Holes By doing this assignment I aim to gain a better understanding of the physics behind Black Holes What is a Black Hole? To understand a black hole, you must first have an understanding of gravity in space. Imagine yourself on a trampoline; you make an indentation in the trampoline fabric. If someone was to roll a ball past you on the trampoline, it would begin to spiral towards you, down into the indent you have made. This is very similar to the way gravity works in space and time. The 'fabric of spacetime' is an imaginary mesh running through space (see right) which can be deformed and warped by the gravity of stars and planets. This is the principle upon which black holes work. A black hole essentially is an incredibly compact body which has warped space-time enough to make any escape from the force of gravity impossible. They are thought to be at the centre of galaxies, including our own Milky Way. As the name implies, a blackhole cannot emit or reflect any light; making them practically invisible. If enough mass is concentrated into a small enough region, the curvature of

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#### The effects of the extension of a spring on the time it takes a weight to oscillate.

The effects of the extension of a spring on the time it takes a weight to oscillate. Introduction I am investigating the relationship between the extension of the spring and the effect it has on the time it takes for the wait on the spring to oscillate. Scientific Knowledge As the spring is extended the spring stores potential kinetic energy. So the larger X is, the more energy is stored. To work out the energy we must work out the amount of work done first: Work Done = Force x Distance When the mass is released the potential energy of the spring is converted into kinetic energy of the mass which is at a maximum when it passes through the mid-point of the oscillation which is the point where the spring is not extended at all. So the work done by the spring is equal to the mass times the acceleration of the mass times the distance. This gives the energy released by the spring: Work Done = mass x acceleration x distance At the centre point Kinetic energy is equal to Potential energy. To work out the kinetic energy: K.E = 1/2 mv2 This is the energy gained by the mass after releasing it on the extended spring. So therefore: /2 mv2 = maX /2 mass x velocity2 = mass x acceleration x extension (distance) The velocity value is the velocity at the mid point which is where the mass final comes to rest after oscillating. The formula can be simplified to: v2 = 2aX Velocity

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#### A report concerning stars and constellations

GENERAL SCIENCE A REPORT CONCERNING STARS & CONSTELLATIONS Report: Michiel Klaassen Joëlle van der Pol Literature essay: Veralyn Adeyinka Wikke den Hartogh 4VM February 2004 Table of contents A few interesting constellations Orion (The hunter) " Orion is the master of the winter skies. He lords over the heavens from late fall to early spring, with his hunting dog Sirius trailing at his feet. " The mythic tales of Orion go as far back as the Hittites, who flourished from the Second Millennium BC to around 1200 BC. One story from this culture account of Orion's death. Here he is called Aqhat, and was a handsome and famous hunter. The Battle-Goddess Anat fell in love with Aqhat, but when he refused to lend her his bow, she sent another man to steal it. This man failed to do it, and wound up killing Aqhat and dropping the bow into the sea. This is said to explain the astronomical fact that Orion and the Bow (an older version of the constellation) drops below the horizon for two months every spring. Finding Orion should be no problem. Its stars are some of the most familiar in all the heavens. There are three bright stars which make up the belt of Orion. From west to east the stars are called Mintaka, Alnilam, and Alnitak. Even the Bible makes reference to this famous group. God, while pointing out how all-powerful he was, is purported to have asked Job if he

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#### Annihilation Theory

The Mystery of Matter and Antimatter Written by Mandy Barbour Year 11 Physics The current unbalanced state of the universe contradicts what our laws of physics have suggested. At the dawn of the universe an imbalance between the originally equal amounts of matter and antimatter occurred, and in 1967 Russian physicist Andrei Sakharov created three conditions that would allow this imbalance to happen. These conditions have been a topic of much debate between physicists and have not been proven to be totally factual to this day. Despite this, they have acted as important guidelines for others involved in this field, proving their relevance. Progress towards understanding the initial state of the universe is increasing and technology is evolving to aid our education. The root to all scientific cosmology is the Big Bang Theory. It is believed that the "big bang" left equal amounts of matter and antimatter. Matter and antimatter is a collective term given to two identical particles that are of opposite charge. Therefore they are the same with the exception of charge. There opposite charges adhere to the Laws of Attraction, which state that two particles of opposing charge are attracted to each other. On their collision they, theoretically, annihilate each other resulting in a gamma ray (pure radiation). This can be shown by; e+ + e- › ? (A positron plus and electron

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