#### Prove if Hookes Law's theory of extension is proportional to length is true.

Aim: The aim of this coursework is to prove if Hookes Law's theory of extension is proportional to length is true. Scientific Knowledge: Robert Hooke investigated springs nearly 30 years ago. He found that the extension was proportional to the stretching force so long as the spring was not permanently stretched. This means that doubling the force doubles the extension, trebling the force trebles the extension and so on. Using the sign for proportionality we can say write Hookes Law as: EXTENSION IS PROPORTIONAL TO STRETCHING FORCE. Prediction: I predict that the extension will be proportional to the stretching force so long as the string is not permanently stretched. This means that the results should be near enough consistent while increasing in the extension until I reach the end of the experiment. Safety Precautions: I am going to make my experiment safe by wearing safety goggles, just incase the spring breaks and bounces back to my eye. Also I am going to keep the experiment in the middle of the table because if the spring passes its elastic limit, the clamp will fall, and might land on your feet. Step-by-Step instructions: * Clamp head to stand, * Connect boss head to clamp, * Fix one circular up to other, * Hook weights up to the spring * Add weights then record extensions after measuring it three times, * Do this with eight different weights, * Record

#### How does the extension of two or more springs in series or parallel compare with the extension of one spring?

How does the extension of two or more springs in series or parallel compare with the extension of one spring? My aim is to find out the extension of a single spring compared with springs in series. I think that the springs in series will extend more than one spring. I think that the springs in series will extend twice as much as one spring. If the extension is x, therefore the load of one Newton on two springs would be 2x as the load of one Newton is on each spring and not shared. One spring is x, two springs in series give 2x as each spring feels the one Newton mass. The parallel share the mass with each feeling 0.5. Parallel is x/2 compared to one spring, x and nx in the series. I will keep this a fair test by keeping the length of each spring the same. I will measure in the same units and keep the same conditions for each experiment. Hooke's Law supports my prediction: "The extension is directly proportional to the load" Equipment List: -springs -weights hanger -Newton weights -stand -clamp -boss -meter ruler Please look at the equipment list and set up as shown in the diagram. I would measure the extension of each spring in series and individually. I would record my results in a table. I will measure each extension three times. I will change the weights and the place of the ruler to stop myself assuming results and to keep them correct and accurate. I

#### Physics - The aim of this practical investigation was to obtain a value for the spring constant k for a decided system of springs.

PH 6 - Physics Coursework Aim The aim of this practical investigation was to obtain a value for the spring constant k for a decided system of springs. Summary A value for k for a chosen spring system was deduced from two separate experiments. The some possible methods were : - .) Hooke's Law - using a set of known masses to stretch a spring system. Deriving k from a Force-Extension graph. 2.) Period of Oscillation of a Mass (SHM) - on a spring system. Using a set of known masses, showing how the period varies with suspended mass. Deriving k from a suitable graph. 3.) Resonance of the spring system - The two k values were then compared and analysed to see which method gives the better value. The two values were 8.09Nm-1 and 7.57 Nm-1. Hooke's Law Theory Using the equation F = kx where F = the force exerted on the spring by the mass in Newtons (N) k = the spring constant in Newtons per millimeter (Nmm-1) and, x = the extension observed in millimeters (mm) I will plot an F-x graph from which I will obtain a gradient and y-intercept which I can use to compare the above equation to the straight line equation y = mx + c where mx = gradient and, c = y-intercept So, y = mx + c F = k + x Therefore, the gradient of my F-x graph, which should pass through the origin, will equate to the k value of my spring system. Diagram for Hooke's Law experiment

#### Hookes law analysis and evaluation

Analysis The results that I have collected have proved very conclusive. From the graphs that have been plotted I have been able to deduce that when a spring is added to the spring in series then the extension increases proportionally, as is proved below: Force (N) Single spring (m) Spring in series (m) 0 0.000 0.000 0.044 0.086 2 0.087 0.157 3 0.130 0.234 4 0.173 .312 5 0.216 0.399 6 0.258 0.481 7 0.278 0.553 8 0.336 0.652 When the load 1N is added to the springs in series the extension is 0.086 m, however when the load is added to the spring on it's own the extension is only 0.044 m. This proves that the equation k = f / x is true. This is because when the load is kept the same but the spring stiffness is doubled then the extension is also doubled. To work out the spring constant I will need to use the equation: K = Force or Load / gradient The spring stiffness is a measure as to how much the string is extended when a load is placed on it. This can be worked out using the equation: K = F / X Graph of my results: The graph that has been plotted (spring stiffness against load) shows that the stiffness of the spring halves when there is single spring but when two are put in series then the stiffness is doubled. It can be seen clearly that the gradient of single spring is almost half of spring in series. Gradient for single spring

#### Estimating the wavelength of light using a double-slit and a plane diffraction grating

Title Estimating the wavelength of light using a double-slit and a plane diffraction grating Objective To project a Young's interference pattern on a screen and make measurements to estimate the wavelength of light To estimate the wavelengths of the different colours of the spectrum produced using a fine diffraction grating Apparatus Instrument Descriptions double slit Mounted on a large cardboard translucent screen Ground glass Compact light source With vertical filament Low voltage power supply ------------------------------------------------- Magnifying glass ------------------------------------------------- 2 metre rule 00 cm vernier caliper Smallest division 0.1mm diffraction grating 3000 lines per cm ray-box Without lens and slit plate Theory Using a double-slit In the Young's double slit experiment, two rays through the slits interfere to give the interference pattern. Bright fringes occur at positions where constructive interference occurs (Fig.1). The path difference from the slits at an angle ? is a multiple n of the wavelength ?, i.e. a sin ?=n?, where n=1,2,3... is known as order number. For small value of ?, Sin?= tan?= s/D Where s is the distance of the fringe from the central line and D is distance from the screen to the double slits. Hence, we have s= nD?/a Consider the nth and the (n+1)th ringes, Fringe separation y= s -s

#### 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

#### Behavior of Waves

Lesson 3: Behavior of Waves Interference of Waves What happens when two waves meet while they travel through the same medium? What effect will the meeting of the waves have upon the appearance of the medium? Will the two waves bounce off each other upon meeting (much like two billiard balls would) or will the two waves pass through each other? These questions involving the meeting of two or more waves along the same medium pertain to the topic of wave interference. Wave interference is the phenomenon which occurs when two waves meet while traveling along the same medium. The interference of waves causes the medium to take on a shape which results from the net effect of the two individual waves upon the particles of the medium. To begin our exploration of wave interference, consider two pulses of the same amplitude traveling in different directions along the same medium. Let's suppose that each crest has an amplitude of +1 unit (the positive indicates an upward displacement as would be expected for a crest) and has the shape of a sine wave. As the sine crests move towards each other, there will eventually be a moment in time when they are completely overlapped. At that moment, the resulting shape of the medium would be a sine crest with an amplitude of +2 units. The diagrams below depict the before- and during interference snapshots of the medium for two such crests. The

#### Qur'an on origin of the universe.

Year 11 RS Qur'an on origin of the universe The science of modern cosmology, observational and theoretical, clearly indicates that, at one point in time, the whole universe was nothing but a cloud of 'smoke', this is what Muhammad claimed of how the origin of the universe was. This is used in defence of Muhamad as he was an illiterate person and especially not a scientist so there was no way he would have known that the origin of the universe was a cloud of smoke. This then proves that he must have been sent the revelations through Allah because there was no way he would have known that. Qur'an on seas and rivers Modern Science has discovered that in the places where two different seas meet, there is a barrier between them. This barrier divides the two seas so that each sea has its own temperature, salinity, and density.1 For example, Mediterranean sea water is warm, saline, and less dense, compared to Atlantic ocean water. When Mediterranean sea water enters the Atlantic over the Gibraltar sill, it moves several hundred kilometers into the Atlantic at a depth of about 1000 meters with its own warm, saline, and less dense characteristics. The Mediterranean water stabilizes at this depth. Although there are large waves, strong currents, and tides in these seas, they do not mix or transgress this barrier. The Holy Quran mentioned that there is a barrier between two

#### Study the interference of light using Helium - Neon Diode Laser.

AIM TO STUDY THE INTERFERENCE OF LIGHT BY USING HELIUM -DIODE LASER COHERENT SOURCES As we see later, light waves from a sodium lamp, for example, are due to energy changes in the sodium atoms. The emitted waves occur in bursts lasting about second. The light waves produced by the different atoms are out of phase with each other, as they are omitted randomly and rapidly. We call such sources of light waves as these atoms incoherent sources on account of the continual change of phase. Two sodium lamps X and Y both emit light waves of the same colour or wavelength. But owing to the random emission of light waves from their atoms, their resultant light waves are constantly out of phase. So X and Y are incoherent sources. Coherent sources are those which emit light waves of the same wavelength or frequency which are always in phase with each other or have a constant phase difference. As we now show, two coherent sources can together produce the phenomenon of interference. INTERFERENCE OF LIGHT WAVES, CONSTRUCTIVE INTERFERENCE Suppose two sources of light, A, B have exactly the same wavelength and amplitude of vibration, and that their vibration are always in phase with each other, fig.1. The two sources A and B are therefore coherent sources. fig.1 Their combined effect at a point is obtained by adding algebraically the displacements at the point due to the sources

#### An Investigation To See If Hookes Law Is Or Is Not reliable.

An Investigation To See If Hookes Law Is Or Is Not reliable Aim: I am going to explore Hookes Law and produce a conclusion of my own whether or not Hookes Law is accurate Hookes Law states that the extension of a spring is proportional to the force applied to it. Prediction: I predict that Hookes Law is true because we use springs to measure things such as we use the Newton metre to measure newtons this uses a spring and if spring weren't accurate to the force applied to it we wouldn't use a Newton metre. I believe each 100g weight will move the spring in equal or round about additions each time i.e. 100g = 1cm extension 200g a further cm or 2 etc. Factors: Factors that may affect this experiment are: * A moving spring * Spring passing yield point * Measuring from same point each time All these may or will affect the results of my experiment and alter the outcome in my conclusion. All these should and will be kept a constant. Apparatus: * A spring * Boss and Clamp * 30cm ruler * 100g weights Diagram: Method: * For safety measures I will stand up during the whole experiment * For fairness I will keep all the above factors a constant and use the same spring throughout. * I will go up in 100g intervals every time until I reach a certain point making sure I do not exceed the springs yield point (where the spring is stretched so far it cannot return to