1. Take one or two wooden blocks and put them under the table to tilt the table. 2. Place the ticker timer at the top of the table but make sure that it should not fall due to the slope of the table. 3. Conect the ticker timer to the electricity appliance. 4. Insert the carbon/paper tape inside the ticker timer. 5. Paste the carbon/paper tape, which is on the front side of the ticker timer, on the backside of the dynamic trolley with a cello tape. 6. Start the ticker timer and release the trolley.
7. Stop the ticker timer when trolley reaches the other end of the table. But assure that before trolley falls down, it must be stopped. 8. Then continue the same procedure three times but with new carbon tape and then record the data. 9. Find the velocities by counting the fifty dots(the ticker timer makes fifty dots in one second). Then by counting first five dots and then measure the length by ruler and then initial speed(u). Similarly by counting last five dots from the fifty dots and then measure it by a ruler and calculate final speed (v). The highest acceleration is 0.62m/s2 and the lowest acceleration is 0.58m/s2 .The average acceleration is 0.603m/s2. There are some uncertainties in measurement.
Evaluations: I had some problems due to accuracy of acceleration as the distance was in very small scales. Moreover I faced difficulty in handling with uncertainties.
– This lab will test the effects of the surface area factor on acceleration due to gravity. Pieces of paper will be dropped down and timed from high point of release, where the release point will be constant to reduce human timing/reaction errors. The paper will be folded proportionally (always half of the previous) to manipulate the surface area; five trials will be recorded – four of the closest results will be put into use as data for this lab.
Hypothesis: The time of descent of the paper will get faster as the surface area of the paper decrease. The increase and decrease in the time of descent should be caused by natural factors such as air resistance acting towards the surface area of the paper in the test environment. Variables: – Manipulated Variable: Surface Area The surface area of the paper will be measured with a ruler before each trial takes place. The surface area will always be measured to the nearest 0.01cm by using a ruler measuring in millimeters and converting it back to centimeters.
Responding Variable: Time of Descent The paper will be dropped with the help of a partner on top of the apparatus at a constant vertical displacement and position (the paper will be dropped horizontally against its surface area). The partner at the bottom of the apparatus will be timing the time of descent of the paper using an electronic stop watch measuring to the nearest 0.01s by reacting to the very first sound of the paper hitting the ground. Controlled Variable(s): Vertical Displacement; Environmental Conditions; Launch Velocity/Position; Mass of Test Subject
The launch velocity will be controlled by the help of a partner on the top of the apparatus (Vi=0) by carefully releasing every piece of the paper against its widest surface area against the air in the same manner every trial so that no extra force is given to the paper before its point of release which may alter its initial velocity. The environmental conditions of the experiment will be controlled by performing all trials in the same hallway with no excess air flow to possibly alter or effect the time of descent of the paper.
The temperature of the test environment will also remain constant, which should help maintain a consistent amount of air resistance that the paper will encounter. The vertical displacement will remain constant at 520.0cm because it will help maintain the time of descent to surface area ratio at a constant throughout the experiment, which will help to answer the problem of this experiment later in the lab report. The mass of the paper used to test will remain with a constant mass to proportionalize the surface area to mass ratio, which will help to compare the final results.
Materials Standard Testing Stop Watch (Measured to the Nearest 0.01s) Standard Measuring Tape (Measured to the Nearest 0.1 cm) Ruled Sheets of Paper by Media Inc. Diagram: Procedure The following procedure will be performed after every transformed surface area. 1. The folded pieces of paper will be dropped from a constant height, in order to minimize the human reaction error when timing the time of descent, the height in which the paper will be released will be relatively high(520.0cms).
2. The paper will be dropped at a constant position and launch velocity, it will be placed flat against its largest surface area, we want to do this because we are constantly changing the surface area and observing its effects in relations to time 3. A partner at the top of the apparatus will drop the paper down at the count of 3 from the partner below the apparatus, as the partner below the apparatus will start the stop watch. 4. As soon as the partner below hears the sound of the paper hitting the floor, he will stop the stop watch and record the time of descent of the paper. 5. The person below the apparatus will record data after each trial; a total of 5 trials will be recorded for every change in surface area.