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
Investigation on whether Rubber obeys Hooke's Rule
Investigation on whether Rubber obeys Hooke's Rule Plan Introduction Hooke's Rule states that extension of a material is proportional to the tension force applied to it unless the elastic limit is reached, which is the point at which the material no longer obeys Hooke's Rule. There are only a few materials that obey this rule. In this investigation, we will find out whether rubber obeys Hooke's Rule. We will measure in detail the way in which the extension of a rubber band depends on the tension in the band. This will be done by applying various amounts of weights, as it is a continual variation. Hooke's Rule = F = ke * F = Force in Newtons * k = Spring constant * e = Extension in Centimetres Rubber is a natural polymer which is made up of long chains of molecules which are bent back and forth with weak forces acting between them. As the rubber band is stretched, molecules straighten out and allow the rubber band to become larger. Eventually, as the molecules become fully stretched, the long chains will become parallel to each other and can stretch up to ten times its original length. Extra force will make the rubber band break. If the rubber is not stretched to breaking, once the force is removed the molecules tend to curl back again into their original position because of the attraction and cross-links between adjacent molecules. The return is elastic. Hypothesis I
The Electromagnetic Spectrum
The Electromagnetic Spectrum The electromagnetic spectrum is the collective name for all types of radiation. Radiation is energy that travels around in waves. The electromagnetic spectrum goes from the waves with the lowest energy to those with the highest energy. Radio Waves Radio waves have the longest wavelengths in the electromagnetic spectrum. They can be from as long as a football to as long as a football pitches. Radio waves carry signals from devices from one place to another invisibly through the air. Radio waves are used for many different jobs: ? In Medicine - radio waves are used to transmit the pattern of a heartbeat through a monitor at a patient's home to a nearby hospital. They are also used to radio the condition of a patient from an ambulance to a hospital. Radio waves are used in medicine when paramedics are dispatched to the scene where they are needed. The hospital can tell the paramedics the condition of the person so that the paramedics can prepare a medical treatment kit. ? In Industry - used mainly in the transportation business. Radio waves can also be used to provide communication on construction sites. ? In Science - radio waves from outside the earth are detected using in radio telescopes. Radio waves are picked up when they hit the antenna of the radio telescope. The wave then goes to the tuner, then to the amplifier, and finally to the
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
The Electro magnetic spectrum.
The Electro magnetic spectrum. By Steve Wyers 11cu Radio Waves Radio waves are made by various types of transmitter, depending on the wavelength. They are also given off by stars, sparks and lightning, which is why you hear interference on your radio in a thunderstorm. Radio waves are the lowest frequencies in the electromagnetic spectrum, and are used mainly for communications. Radio waves are divided into:- Long Wave, around 1~2 km in wavelength. The radio station "Atlantic 252" broadcasts here. Medium Wave, around 100m in wavelength, used by BBC Radio 5 and other "AM" stations. VHF, which stands for "Very High Frequency" and has wavelengths of around 2m. This is where you find stereo "FM" radio stations, such as "Galaxy 101" and "GWR FM". Further up the VHF band are civilian aircraft and taxis. UHF stands for "Ultra High Frequency", and has wavelengths of less than a metre. It's used for Police radio communications, military aircraft radios and television transmissions. Large doses of radio waves are believed to cause cancer, leukaemia and other disorders. Some people claim that the very low frequency field from overhead power cables near their homes has affected their health. Microwaves Microwaves are basically extremely high frequency radio waves, and are made by various types of transmitter. In a mobile phone, they're made by a transmitter chip and an antenna,
See how one factor affects the period of time a mass on the end of a spring takes to complete one whole oscillation.
Physics Coursework Planning Variables The aim of these experiments will be to see how one factor affects the period of time a mass on the end of a spring takes to complete one whole oscillation. One whole oscillation means the mass returning to its original position, be it the equilibrium or not. I will look at the independent variables (variables which are not caused as a result of another variable). The dependent variable in this case is time * Mass - the size of mass on the end of the spring. Bigger mass may affect the time it takes * Length of spring - if the spring is longer, the mass would have further to travel and this will affect the time it takes to oscillate. * Tension of spring - the more tension in the spring may result in the mass oscillating faster as there would be more tension. This would prevent the mass pulling the spring too far and thus mean the oscillating time would be shorter. * Gravity - the force of gravity would affect the mass, as if the gravity was less the mass would take longer to pull the spring down. If the gravity were stronger, the mass would take longer to go back to the equilibrium. * Temperature - if the temperature changed, the spring would be more ductile and this could mean the spring would deform earlier than it would at room temperature. I have chosen to make mass the variable, as this is the easiest variable to use in
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
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
The Science of Soundwaves and Their Applications
The Science of Soundwaves and Their Applications The science of the sound wave is important in everyday life, from its use in car mufflers to the high tech office. In this paper I'm going to talk about the sound wave and describe its characteristics, show how this science was applied to muffler design, and computer design. Sound is a pressure wave that consists of tiny fluctuations in the air pressure. The amplitude in general, is the maximum change in value of a parameter during the oscillation of a wave. In amplitude, that parameter will usually be pressure. The amplitude of a sound is the loudness of the sound. In illustration, this is the distance between a peak or trough. See illustration on previous page. The frequency is defined as the number of vibrations, oscillations, or cycles in a repeating process occurring per unit time. In the context of sound, it is the number of compressions passing a fixed point of reference in one second. The resulting unit of frequency is called Hertz (Hz). Frequency is perceived as pitch. Intensity is the rate at which sound energy flows through a defined area. Since the flow of energy is power, the dimensions of sound intensity are power/area. Usually, sound intensity is measured in watts/meter2. Intensity is perceived as loudness. Interference is a synonym for superposition. Constructive interference is the amplitude of the
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