Assessed Experiment on the Efficiency of a Ramp.

Graeme Abbott 10E Assessed Experiment on the Efficiency of a Ramp Planning I am investigating the efficiency of a ramp depending on the mass of the load , the height of the ramp or the angle. I have chosen the amount of load to be lifted up the ramp because I think I can get a more accurate set of results this way. The ramp is a basic but very effective way of moving objects to a greater height more easily than simply lifting. Fair Test * I will take all of my results on the same day with the same equipment and area. * I will repeat my test three times for a more accurate test. * I will pull the bucket along at the roughly same steady speed every time. * I will take the results myself so they will not differ. A fair test is important in all investigations because otherwise the results will not be reliable. A fair test should avoid being biased and enable repeatability. Prediction The variable that I have chosen is the increase in masses and therefore weight to the bucket. I would predict that as the mass increases the force required to achieve a constant speed will also increase. As the mass is increased the friction between the bucket and the ramp increases. Gravity is a constant force on all masses the incline is the same for each increase in mass. To overcome the resistance of the inclined surface the force is greater for larger masses. If all

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  • Level: AS and A Level
  • Subject: Science
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Checking Newton’s 2nd law of motion

Checking Newton's 2nd law of motion In this experiment I will make measurements on a two - pulley system and use them to check Newton's 2nd law: 'The rate of momentum of a body Is directly proportional to the external, Resultant force acting upon it. The change in momentum takes place in the Direction of that force. The apparatus is set up as shown in the diagram below: The masses m1 and m2 are initially set at 400 grams each. The ruler is set vertically. I measured and recorded the distance (S). There must be the same friction at the pulleys; in order to comply with this took added 10 grams masses to m1 until the two masses jus begin to move. I recorded the extra masses m0 added, and the total mass M of m1 and m2. I then held m1 by hand, added one 10g mass, and released it. My partner at that exact moment started the stopwatch. When the m1 hit the soft material the stopwatch was stopped. I recorded the time taken in the table below and repeated this a further one more time so I could finally take an average reading. Extra mass added to m1 Time 1 s Time 2 s Mean Time Time² s² /(m Kgs-1 0.020 3.0 4.18 3.59 2.8 50 0.040 .60 2.14 .87 3.49 25 0.060 .62 .45 .53 2.34 6.6 0.080 .19 .30 .24 .53 2.5 0.100 .19 .0 .09 .18 0 On then ext page is the graph that I plotted with t on t on the y- axis against 1/(m on the x- axis. Theory:

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  • Level: AS and A Level
  • Subject: Science
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Physics in Sports. The law of conservation of energy also plays a major role in sports. In football if you kick a ball you are transferring kinetic energy from your foot to the ball.

The importance of physics in Sports Everything from kicking a ball into a goal to running from one side to the other side of the field is based on physics. Physics plays a key role in sports; it can impact on a player either positively or even negatively. Gravity, friction, motion and projectile affects sport in every aspect. How physics affects Sports No matter how hard or high you kick a ball as a result of gravity it will be pulled back down to earth. Although the rate at which it descends may vary on its mass and surface area, it will still have to come down. If thrown at any other angle than 90° it will have a parabolic path (trajectory). Also air resistance and friction will reduce the rate at which the ball moves. The law of conservation of energy also plays a major role in sports. In football if you kick a ball you are transferring kinetic energy from your foot to the ball. From the pendulum balls by the side you can see how energy transfer works. If you lift the ball at left then energy will be passed on to the neighbouring ball and as a result the ball at the end will move the same distance from which it was released on the other side. Similarly in this diagram the character kicks the ball transferring kinetic energy from his foot to the ball. The ball moves and rises and therefore the kinetic energy will be converted into gravitational potential energy.

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  • Level: AS and A Level
  • Subject: Science
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Explain how excessive exposure to radiation can cause harm.

M4 – Explain how excessive exposure to radiation can cause harm. The amount of radiation given to patients in diagnosis is dependent on how close vital organs and tissues are to the malignant tumour, there are two terms commonly used by scientists when dealing with radiation doses, absorbed dose, the amount of energy received by a mass of tissue, which is measured in kilograms (Kg), It has the unit J/Kg and is called the gray (Gy). Effective dose, if the ionising radiation types are compared using the same amounts of energy, alpha particles cause much biological damage, 20 times more damage than X-rays. In medicine radiation affects different tissues and organs in different ways and so each tissue or organ has a number which is used as a quality factor, the absorbed dose is multiplied by this number to give the figure for effective dose, also measured in J/kg b called Sievert (Sv). Major effects of ionising radiation on the body Injury to living tissue results from the transfer of energy to atoms and molecules in the cellular structure. Ionizing radiation causes atoms and molecules to become ionized or excited. These excitations and ionizations can: . Produce free radicals. 2. Break chemical bonds. 3. Produce new chemical bonds and cross-linkage between macromolecules. 4. Damage molecules that regulate vital cell processes (e.g. DNA, RNA, proteins). The cell can

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  • Level: AS and A Level
  • Subject: Science
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Gravitation - Kepler and Newton revision notes and calculations.

Gravitation Kepler (1571-1630) has studied for many years the records of observation on planets and summarised three laws. Kepler's Law (1) Each planet moves in an ellipse which has the sun at one focus (2) The line joining the sun and the moving planet sweeps out equal area in equal time (3) the square of the time of revolution of any planet (i.e. T) about the sun is proportional to the cube of the planets' mean distance from the sun I.e. is a constant Interpretation form Kepler's laws (I) Kepler's second law : The area swept out in a very short time interval (?t), neglecting the small triangular region is A The rate of area swept = Hence it is a constant. Compare this equation with the angular momentum = Constant This law is in fact an evidence of conservation of angular momentum. (II) Kepler's third law About 1666, Newton investigated the motion of the moon, and thought that it was the force of gravity to pull the moon and keep it in its orbit NB: Time between full moon is 29.5 days but this due to the earth also moving round the sun, the moon is therefore to travel a bit longer At the earth? surface g=9.81m . This is due to the fact that we are nearer the earth centre than the moon (about 1:60) Newton wanted to find out a relation between the distance and the gravitational force (of acceleration due to gravity g) First trial: Second

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  • Level: AS and A Level
  • Subject: Science
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Radiocarbon Dating

Radiocarbon Dating ________________ Radiocarbon dating is a chemical analysis used to determine the age of organic materials based on their content of the radioisotope carbon-14, to estimate the age of carbon-bearing materials up to about 58,000 to 62,000 years. Archaeology and other human sciences use radiocarbon dating to prove or disprove theories. Over the years, carbon 14 dating has also found applications in geology, hydrology, geophysics, and atmospheric science. Not all materials can be radiocarbon dated. Most, if not all, organic compounds can be dated. Samples that have been radiocarbon dated since the inception of the method include charcoal, wood, twigs, seeds, bones, shells and water, among others. When plants during photosynthesis they include a certain amount of 14C, the isotope in the atmosphere matches the same level approximately. Through photosynthesis Carbon dioxide is taken in by the plant, which is also ingested by animals, therefore every living organism is continually exchanging carbon-14 with its surrounding area as long as it lives. On the other hand when the organism dies the exchanges stops, so the amount of carbon-14 slowly decreases by radioactive beta decay with a half-life of 5,730+-40 years, half-life is the period of time it takes for the amount of a substance undergoing decay to decrease by half. There are three main types of techniques

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  • Level: AS and A Level
  • Subject: Science
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The egg drop challenge is not mostly a "shock absorption" exercise; the springiness of the padding around the egg is the determining factor.

Egg Drop Contest Materials List 2 small foam cups 2500 square centimeters of plastic bubble wrap 25 paper tissues 12 cm3 cardboard box Abstract of Physical Principals The egg drop challenge is not mostly a "shock absorption" exercise; the "springiness" of the padding around the egg is the determining factor. A bus without springs is near impossible to drive, while one without shocks feels almost normal until moments when the shocks are needed. What will break the egg is to have a force on the egg greater than the shell can withstand. This can be avoided by distributing the force evenly across the egg's surface. The shell is very strong if the force is well distributed, and very weak if the force is all at one point, or on a small area. You can pierce the egg with a very small force with a needle, yet you can put it between your palms and push with great force without breaking it. If your "padding" is too soft, it will work well until the padding has compressed, and then the egg will experience a large g-force and break. If your padding is too hard, then the egg will break while the padding is being compressed. What is desired is padding that will compress at a rate that gives the egg the longest time to stop. We believe that the best solution is to have increasingly soft padding surrounding the egg in multiple (in our case, 3) layers. Our guess is that firm foam

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  • Level: AS and A Level
  • Subject: Science
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Force and Newton's three Laws

Force and Newton's three Laws We have all known from a young age that an acceleration is caused by a push or a pull. Today we will express this more qualitatively in 3 laws which are called Newton's Laws. Newton's first Law. Newton's first law really harks back to the early 17th century. It was Galileo who expressed what he called the law of inertia, he stated: "A body at rest remains at rest and a body in motion continues to move at constant velocity along a straight line unless acted upon by an external force." Now you can read Newton's own words from his famous book Principia: "Everybody perseveres in its state of rest or of uniform motion in a right line unless it is compelled to change that state by forces impressed upon it." The problem is that Newton's 1st law goes clearly against our daily experiences; things that move don't move along a straight line, nor do they continue to move for ever. The reason for this is gravity; and there is another reason too, even if you remove gravity there is still friction, and there is air drag. So things will always come to halt. But we believe, though, that in the absence of any forces, that an object, if it had a velocity, would continue along in a straight line forever, and ever, and ever. Warning advanced ideas may be found in the following ... However Newton's first law, this profoundly fundamental law, does not hold in

  • Word count: 2569
  • Level: AS and A Level
  • Subject: Science
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Galileo's Rolling Ball experiment

Galileo's Rolling Ball experiment Aim: Galileo in his rolling ball experiment investigated the acceleration of a ball rolling down an inclined plane, using a similar setup I will investigate how the time taken to roll down the inclined plane varies with the vertical height change. Theory: When two similar objects are thrown vertically downwards, they are in a state of free-fall. Both objects will hit the ground simultaneously; the force which causes these objects to fall down is the pull of gravity which is also the acceleration of these objects. As the object falls down, its speed increases hence its acceleration increases. Using the equation of motion; S= u t + 1/2 a t2 Since u = o, we can ignore initial velocity so: S = 1/2 a t2 Straight line equation: y = m x + c The variables in this experiment are: S and t2 When compared with the straight line equation: S = 1/2 a t2 y = m x a sin a cos sin = Component of acceleration down slope = g S = 1/2 (a sin) t2 Re-arranging the formula gives: S = 1/2 g t2 = = 1/2 g t2 y-axis gradient x-axis relating this to the equation of a straight line. If t2 is plotted at x-axis and at y-axis the gradient (m) will be equal to 1/2 g therefore, changing the height of the inclined slope and measuring the time period, the value of 'acceleration' can be calculated. =

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  • Level: AS and A Level
  • Subject: Science
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Motion of a sprinter during a 100m run

Investigation 6.1 Motion of a sprinter during a 100m run Distance moved (m) Time at this point (sec) Time interval for previous 10m (sec) 0 0 0 0 2.50 2.50 20 3.65 .15 30 5.06 .41 40 6.50 .44 50 7.83 .33 60 9.48 .65 70 1.90 2.42 The runner starts off slowly and her speed builds up. This is the curve at the bottom of the graph between 0 and 3 seconds it shows that she is accelerating. Her speed is quite consistent between 3 and 9 seconds. This is the relatively straight part in the middle of the graph. After nine seconds her speed reduces slightly until she reaches the end. This is the curve at the top of the graph and it she that she is decelerating. The gradient at 1.0 seconds is; 51.6 = 3.125 The gradient at 5.0 seconds is; 81.2 = 6.6 These values show that he runner is faster at seconds then at 1 second, as the gradient at 5 seconds is much steeper. Section of race (m) Speed for the section (ms-1) Time at the middle (sec) 0-10 4 .25 0-20 8.7 3.075 20-30 7.09 4.355 30-40 6.94 5.78 40-50 7.52 7.165 50-60 6.06 8.655 60-70 4.13 0.675 In the first two seconds the performer is rapidly gaining speed. She is accelerating from a still position to a speed of 5.2 (ms-1). Her maximum speed is 7.7 (ms-1) she reaches this speed at 6.4 seconds into the race. In the last three-quarters of the run she reaches her maximum speed and it

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  • Level: AS and A Level
  • Subject: Science
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