The diameter of an impact crater Essay Example for Free

The diameter of an impact crater Essay For example if I unreliably choose to use a constant height of 30cm without any preliminary work, a problem may arise during the experiment where there isnt a major difference between the different recordings for the varying masses, which wouldnt produce results as intended. The independent variable, mass, also needs to be covered in my preliminary work to determine the best range of values I will set it to for the actual experiment. Also this will make it easier for me and save time later as I would already be familiar with the composition of the balls. Preliminary work will also allow me to identity any arising problems at an early stage and determine the required apparatus needed to complete the experiment. Preliminary results: Varying height HEIGHT (CM) DIRECTED SURFACE MASS (G) CRATER SIZE (MM) 1 2 3 Mean 20 Fine aquarium gravel Golf ball (42) 65 64 63 64 40 Fine aquarium gravel Golf ball (42) 86 86 87 86. 33 60 Fine aquarium gravel Golf ball (42) 93 93 92 92. 66 The table shows that as the height at which the ball is dropped from increases the crater size also increases. However from the preliminary work I have decided that I will keep a constant height larger than the ones tested. This is so more disperse results will be produced which will make the results clearer in order to notice any trends. Varying directed surface DIRECTED SURFACE HEIGHT (CM) MASS (G) CRATER SIZE (MM) 1 2 3 Mean Fine aquarium gravel 50 Golf ball (42) 91 91 92 91. 33 Silver sand 50 Golf ball (42) 93 94 93 93. 33 Fine sand 50 Golf ball (42) 94 94 94 94 As can be seen from the table, there is not much difference between the crater sizes produced when the golf ball is dropped into different directed surfaces. However if my intervals of height were higher then more disperse results would most likely be produced. Varying mass MASS (G) HEIGHT (CM). DIRECTED SURFACE CRATER SIZE (MM) 1 2 3 Mean Ping pong (2. 6) 50 Fine aquarium gravel 42 42 40 41. 33 Plasticine (29. 1) 50 Fine aquarium gravel 64 62 63 63 Golf ball (42) 50 Fine aquarium gravel 92 93 92 92. 33 As can be seen from the table, mass has a significant affect on the crater size. Amongst the balls I was to experiment during my preliminary was a steel ball, however initial testing showed that the ball sunk right into the directed surface which would have made it difficult to measure accurately. So I replaced it with plasticine, and I discovered that the size of the plasticine could be altered in order to vary the mass. So I was able to alter the size to match a similar mass of a steel ball. The usefulness and findings of my preliminary results, in accordance to the actual experiment, can be found in the variable table below: Dependent Variable value how measured Crater size Centimetre (cm) Recording should be repeated twice Vernier caliper Independent Variable Mass Grams (g) 5-35 Electric scale Control Variables Height Centimetre (cm) 100 constant Metre ruler Directed surface Fine aquarium gravel constant As mentioned earlier, using plasticine I am able to alter the mass to a range required. This is primarily the reason why I have chosen to use plasticine constantly throughout the experiment. By means of altering the mass for each recording I will be able to pre-set the intervals by 5g as required. Whereas if I were to use different balls I wouldnt be able to present a range of results through varying ranges. METHOD: I am now able to verify the apparatus needed to complete the investigation: Large plastic tray   Fine aquarium gravel to fill the tray   Plasticine Meter ruler to measure height   Two stand, bosses clamps to hold metre ruler and plasticine ball   Standard ruler used for leveling of aquarium gravel. Electric scale to measure mass of plasticine   Vernier caliper to measure crater size   Safety goggles (optional)   Set square (optional) Below is a diagram showing how the apparatus should be set up: The following steps will need to be carried out in order to conduct an accurate and more importantly successful experiment: 1. Begin by setting out the apparatus as shown in the diagram above. It is required that 1/3 of the plastic tray is filled with the provided fine aquarium gravel. 2. Ensure that the boss of the clamp is positioned directly above the surface so an attached ball will fall directly below onto the surface. 3. Knowing the first range of mass is 5g, using the plasticine adjust the size until the mass totals 5g on the electric scale. 4. Tighten the plasticine ball to the boss of the clamp ensuring that it is positioned at 50cm height. A set square can be used to ensure the ball is placed at a straight angle. 5. Using the standard ruler provided smooth the fine aquarium gravel so it is level. 6. Now ensuring that the plasticine is positioned at the correct height (50cm), it is placed at a straight angle and the surface is smooth, loosen the boss and the plasticine should fall onto the surface using the force of only gravity. 7. Without putting any pressure on the ball, remove it from the surface. 8. Finally using a vernier caliper measure the diameter of the created crater. The results of this should be recorded into the results table. 9. In order to produce the most accurate results possible, repeat stages 3-8 twice more using the same mass of plasticine. However it is required the mass of plasticine is measured again as this may have changed during the first recording. 10. Repeat the whole experiment again but stage 3 should be altered so the mass of plasticine is 5g heavier than the one before. This procedure should continue until you have recorded final results for 35g. Safety is not a major factor to take into consideration. However it is optional to wear safety goggles in order to avoid a rare occasion of any fine aquarium gravel coming into contact with eyes. And as usual general safety will need to be carried out by placing bags away from the area used for the experiment and ensure the desk is cleared of all books and stationary.  Fine aquarium gravel   Fine aquarium gravel. Fine aquarium gravel   Fine aquarium gravel Fine aquarium gravel   Fine aquarium gravel   found that altering the size of the plasticine to match the required range was time consuming and at times recordings had to be repeated as the mass wasnt accurate. However using plasticine gave me additional independent control than I would have had if I used a range of different balls.