Pendulum Investigation.
Task: To find out if the length of the string or the mass that it carries affects the movement and the speed of which it swings. Variables: The weight, length of string, wind (caused by air conditioners), how much the string is twisted, friction between thread and clamp. Invariables: Clamp, string, measuring equipment, stopwatch, person who does all the measuring and timing, weights, position where knot is tied, angle where it is released (amplitude). Prediction: We predict that as the mass that the string carries increase, the speed that the sting swings will also increase. We think that this is because as there is more weight pulling it downwards as it gets higher. Also, we predict that as the length of the string decreases, the swing speed will increase as the string is shorter. We think that this is because as the string is shortened, it is closer to the pivot which means that it would swing faster. Diagram of Apparatus: Method: 1. Setup apparatus as shown above 2. Set the amplitude as 45 degrees 3. When pendulum passes the centre for the first time, that counts as 0 4. Keep on counting until required swings are met (1 or 10) 5. Change variables and repeat experiment 6. Note down all measurements in results table Errors in Measuring/Judgment: In many cases we found that when we repeated the experiments, we found that the time or the amplitude was different.
Pendulum Investigation
? Planing Method: For this investigation you will need :- ? Metre ruler ? Clamp stand ? Stop clock ? String ? Weight Set up a clamp stand with a piece of string attached to it. 2 The weight need to be attached securely to the end of the string. 3 The weight will be held to one side at an angle and then released. 4 A stop clock will be used to time taken for one full oscillation. 5 This will be repeated a number of times for one full oscillation, each time shortening the length of string by 10 cm. One full oscillation The diagram of the pendulum I am going to record the results into a table like this:- Times for 5 oscillations in seconds Length st experiment 2nd experiment 3rd experiment Mean 0cm 20cm 30cm 40cm 50cm 60cm 70cm 80cm 90cm 00cm Predictions: - I predict that the time will be affected by the length of the pendulum and also affected by the weight. I based my prediction on the scientific theory that I found in a book. The time is affected because the pendulum is able to work when the bob is raised up at an angle larger that the point at which it is vertically suspended at rest. By raising the bob, the pendulum gains Gravitation Potential Energy, as in being raised, it is held above this point of natural suspension and so therefore is acting against the gravitational force. Once the bob is released, this gravitational force
Pendulum investigation
Pendulum investigation Plan Aim To investigate how the length of a simple pendulum will affect the time for a full swing. Variables Length The length of the pendulum has a large effect on the time for a complete swing. As the pendulum gets longer the time increases. As the pendulum gets shorter the time decreases. Air resistance A big and light pendulum bobble would be affected by a major amount of air resistance. This might cause the pendulum to move in a different way. With a little pendulum bobble there is very small air resistance. This can easily be observed because it takes an extended time for the pendulum to stop swinging, so only a small amount of energy is lost on each swing. Gravity The pendulum is motivated by the force of gravity acting on it. The more gravity the shorter time it will take for a complete swing. The less gravity the longer it would take for a complete swing Size of swing The size of the swing does not have large effect on the time. Mass The mass of the pendulum does not affect the time at all. Prediction The diagram shows the arcs through which two pendulums swing. The red one is twice the length of the black one. The black arc is always at a steeper angle than the red arc, and always above it. The black pendulum has the most gravitational potential energy at the top of the swing because it is higher. This means the
Photosynthesis Investigation
Photosynthesis By Alun Tweedale Introduction Photosynthesis occurs only in the presence of light, and takes place in the chloroplasts of green plant cells. Photosynthesis can be defined as the production of simple sugars (glucose) from carbon dioxide and water, which then release sugar and oxygen. Belo is the chemical equation for photosynthesis: light 6CO2 + 6H2O C6H12O6 + 6O2 Photosynthesis will only take place in the presence of chlorophyll. All plants need light in order to photosynthesise (this is proven in many times in experiments) and so without light the plant would die. The light intensity affects the rate of photosynthesis is because as light, falls on the chloroplasts in each leaf and is trapped by the chlorophyll. This makes the energy available for chemical reactions in the plant. Which means as the amount of (sun)light (Light from the bulb) falls on the plant, more energy is absorbed, so more energy is available for the chemical reactions and so the quicker the rate of photosynthesis can occur. I have discovered that there are four ways in which the rate of Photosynthesis can change: . Light Intensity 2. Carbon Dioxide availability 3. Water availability 4. Temperature In our experiment we will use the amount of Oxygen produced because we can measure this easily and that it is a by-product of photosynthesis. Aim The aim is to find out
Photosynthesis Investigation
Biology Aim of the Experiment The aim if this experiment is to see if changing one of the variables of photosynthesis will affect the pondweeds rate of photosynthesis. Variables that can affect the rate of photosynthesis: Light duration Photosynthesis is only affected by light duration in that it only occurs during periods of light. Light intensity Very high light intensities may bleach chlorophyll and so make photosynthesis impossible. Carbon dioxide concentration CO2 diffuses into the leaf through the stomata from the atmosphere. This is one of the main things used in photosynthesis and without it photosynthesis can't take place. Temperature Many reactions within photosynthesis are controlled by enzymes and therefore temperature sensitive. Enzymes work best at 37.5? and stop working at about 47? because they start dying. Chlorophyll concentration Chlorophyll is one of the main chemicals used in photosynthesis. Chlorophyll is not normally a limiting factor but it can become one if the levels are abnormally low. Iron, magnesium, nitrogen and sunlight are necessary for chlorophyll production, so if the plant is in an area where there is a little of one of these things then the plant could have a lack of chlorophyll and ?naturally have a lower rate of photosynthesis. Pollution Low levels of ozone and sulphur dioxide can damage some plant leaves. Also some
Photosynthesis Investigation
Photosynthesis Investigation Prediction The equation for photosynthesis is: Water + Carbon Dioxide Glucose + Oxygen 6H2O (l) 6CO2 (g) C6H12O6 (aq) 6O2 From this equation it is seen that sunlight is very important in the production of glucose. If all other products are available e.g. water and carbon dioxide in sufficient quantities then light can be used as a variable. If not enough of any reactant is present it will be a limiting factor. This means that no matter how much light is added no more glucose can be made. In our experiment the plant i.e. elodea is placed in water and sodium hydrogen carbonate is added thereby preventing a limiting factor. This is because the water of course is plentiful and the sodium hydrogen carbonate provides the elodea with carbon dioxide. The only way that a limiting factor can be reached is if the temperature rises too high. To prevent this we placed a beaker in front of the light source, which absorbed the heat. The beaker also prevented an increase in temperature as the lamp was moved closer to the elodea. The introduction of the beaker stopped an additional factor entering the experiment. As a limiting factor is unlikely to occur I anticipate that there will be a positive correlation between the rate of photosynthesis and the light intensity. This means that as the light intensity doubles the rate of
Photosynthesis Investigation
Photosynthesis Investigation AIM: As part of my coursework my aim is to produce a detailed investigation showing you what affects photosynthesis and how fast a plant can photosynthesise. To do this I will place pondweed in a bottle and by using a lamp, I will move the light closer to the plant, and count how many bubbles the weed release after a certain amount of time. INVESTIGATION: Photosynthesis is a method in which plants use to produce food. Plants do this by converting light energy to make food from carbon dioxide and water. Inside the leaf is a green substance called Chlorophyll. This Chlorophyll helps to trap the energy from the sunlight, where as the carbon dioxide is trapped through tiny hole in the leaf. The water is absorbed through the roots and up through the stem. The trapped sunlight helps the carbon dioxide and water react. This makes a sugar called glucose. It also makes a waste product called oxygen, which humans use to breathe. The factors that will affect photosynthesis are darkness and this is why they don't photosynthesis at night. At night thought the plants take in oxygen and then give at their carbon dioxide as a waste product. FAIR TESTING: The variables in which I believe will affect my investigation are the following: * Light Shining through from other experiments. This will affect my experiment because the extra light will cause the plant
Photosynthesis Lab
Photosynthesis Lab Jillian Wilson Framingham State College March 29th, 2002 Introduction Photosynthesis is a very important process. It uses sunlight, Carbon dioxide, and water to make food, and gain energy. The process occurs in three stages: the capturing on energy from sunlight, the formation of ATP (from that energy), and the synthesis of CO2 (by use of ATP). The equation for photosynthesis can be written as: 6CO2 + 12 H2O + light energy --> C6h1206 + 6O2 + 6H2O But why is it important? By releasing oxygen and consuming carbon dioxide, photosynthesis has transformed the world into the hospitable environment we know today. Both directly and indirectly, photosynthesis fills all of our food requirements and many of our needs for fiber and building materials. The energy stored in petroleum, natural gas and coal all came from the sun via photosynthesis, as does the energy in firewood, which is a major fuel in many parts of the world. This being the case, scientific research into photosynthesis is vitally important. In this lab, we studied the effects of light intensity on photosynthetic rate, and the relationship between color (essentially light wavelength) and photosynthetic rate. This was an interesting process as it involved the measuring of bubbles released from a plant under water, thus determining the rate of photosynthesis by the amount of oxygen released. The
Physics coursework
Physics coursework Centre 40209 Candidate 3014 Anthony Brocklesby Aim * To investigate the factors that affects the average speed of a falling cake case. Equipment I will need: * 50 cake cases * 1 Stop clock * Flat surface * Tape measure Prediction * I predict 50 cake cases will fall with a greater speed than the others. This is because more cake cases have a greater mass and will therefore hit the floor with a quicker time, and a greater speed. My research suggests that because the mass is greater with more cake cases, they will reach a constant speed slower therefore accelerating for longer. * To calculate the average speed I used the equation o Speed = Distance Time * The distance I am dropping the cases from is 1.8 metres Preliminary plan I will get 50 cake cases * Measure the height of where I want to drop cake cases off. * Use a timer and time the time it takes for the cake case to fall to the floor of the determined height. * Then record my results in a table then determine the average time by adding my first and my second times then dividing them by two * Then to find the average speed I used the equation speed =distance over time * So I divided my distance by my average time to get the average speed. Safety To keep the experiment safe I will make sure that the cupboards are secure and wont fall over. I will also keep the experiment area clear
Physics Coursework
Conclusion on the distance travelled by the car to the height up the ramp From the pattern on the graph we can conclude that the distance travelled by the car is further when you put the car higher up the ramp. We can prove this from the results on the graph. At ten centimetres up the ramp, the car travels an average distance of one hundred and seven point three centimetres. This is quite a low average of distance travelled and that is because there is less gravitational potential energy. As we get higher up the graph we find that the average distance does get larger, this is because there is more gravitational potential energy, and at twenty centimetres up the ramp there is almost a ninety centimetre difference of average between the lowest average and the highest average. This is because there is the most gravitational potential energy for the car. From the graph we can see that the gradient is larger at points fifteen centimetres on the average to fourteen centimetres on the average, then at seventeen centimetres on the average to twenty centimetres on the average. This because the car is starting to reach its terminal velocity and the amount of gravitational potential energy that is being increased is starting to become less effective because the car can not travel any faster after it has reached its terminal velocity. The gradient between points nineteen centimetres on
