BCC g Project

Today, the team continued analyzing the videos from the previous day to determine if the various positions of pitch and tilt on the camera affected the data which can ultimately cause an error in the g value. The videos from the previous day, as mentioned in the last post, contained videos shot with a 20 and 30 degree tilt on the phone as well as a front and backwards pitch of the phone separately (the apparatus and procedure is shown much clearer in the previous post.) The acceleration due to gravity from videos with front and backwards pitch had a noticeable trend of a decreased value of g. This trend may be due to the fact that the camera was pitched front or backwards causing a distorted view of the meter stick -which acts as our scale in the video; having an inaccurate scale will subsequently cause inaccuracy in data. Therefore, it is imperative to have zero pitch to get the most accurate results. Next, the team analyzed videos shot from a 20 and 30 degree angle and discovered...

Figure 1. The Setup The team continues to use PASCO to analyze videos and continues to write the lab manual. Additional videos were recorded today with the camera tipped at different angles in different dirctions to see how the gravitational data would be affected. We took approximately 30 videos. Before performing the trials, we noticed the meter stick we were about to use is bent and not straight. Since this may have caused the error in g that we saw yesterday.  We replaced the bent meter stick with a straight one for our measurements today. The first angle was to pitch the camera back using two tabs as seen in Figure 1. The purpose of this is to study and compare the effects of the data with the camera at different positions. Figure 2. Camera Pitched Back Next, the tab tilts the phone holder forward. See Figure 3 for visualization.   Figure 3. Camera Pitched Forward Later, the phone was angled at 20 degrees and then 30 degrees to the right. A protra...

Yesterday, the team studied the trend of gravitational acceleration values as masses of the balls differed. They also realized the importance of dropping the balls in parallel with the meter stick. So, today the team replicated the experiment keeping all the past discoveries in mind before moving onto the write-up stage. Like the other times, the team dropped the lead, steel, golf, wooden, and hollow plastic balls to check if they would be able to reproduce the same results as the previous trials. However, this time we took two trials for each ball to see the consistency. Figure 1. Snapshot of PASCO Capstone file analyzing the video of the falling steel ball trial #3. To the right is the graph of Velocity vs Time for the falling ball. As mentioned previously, the slope (m) of the best fit line of the Velocity vs Time graph will be our experimental acceleration value. As you see in the figure above, the gravitational acceleration for the falling steel ball is determined to be -9....

The last videos were analyzed using PASCO Capstone. We notice inconsistence in g values for different masses. Thus, we plan to study the results for particular masses by performing additional trials on Monday. Image 1 displays a screenshot of a table in Excel. The table mentions the object's (ball's) type including lead, steel, golf, wood, and hollow plastic toy ball corresponding to it's experimental gravitational acceleration value.  Image 1 . Screenshot of Excel Table The first graph, Figure 1, was created using Microsoft Excel. It displays data with the relationship between gravitational acceleration and mass of lead, steel, wood, golf, and hollow plastic toy ball.  Figure 1. Gravitational Acceleration vs Mass of Various Balls. As described in yesterday's blog, we measured the effect of dropping the ball not even with the meter stick. Figure 2 presents the second graph created on Microsoft Excel. Our data for the steel ball is exhibited below. Neg...

Today the group continued to analyze the five different balls in positions dropped from 10 cm in front of the meter stick, 10 cm behind the meter stick, and in line with the meter stick. All videos were analyzed using the Pasco Capstone software which utilizes plotted points to find various calculated data -in this case, the group is tasked with finding the acceleration due to gravity. As mentioned previously, two major determining factors contribute to the accuracy of the calculated acceleration value: where the ball moves (and lands) in relation with the meter stick (which acts as the scale to determine the distance traveled by the ball) and the air resistance of the ball which acts against the force of gravity, thus causing a noticeable difference in results when comparing to the actual value of g as well as calculated values from heavier objects such as a lead ball. Figure 1:  lead ball 10 cm behind meter stick Figure 2:  lead ball in line with meter stick ...

Date: May 29th, 2018 It is extremely important to be very careful while taking measurements during science experiments. So, today the team explored the possibilities of errors included in the previous trials and ways to avoid them during the experiment. After recording 26 slow-motion videos and analyzing them, we realized how important it is to drop the objects in level with the meter stick. To prove our hypothesis from yesterday's blog, we marked the floor at certain distances (10 cm, 20 cm & 30 cm) in front of and behind the meter stick, and dropped different balls (golf, steel, lead, wooden and hollow plastic ball) from right above the marks on the floor.  We chose balls of various masses to determine the effect of air resistance on our results. After analyzing selected videos for these trials, we noticed a pattern: the balls dropped behind the meterstick ended up giving us a lower value of acceleration due to gravity than the accepted value, and the ones dropped in fr...

The team used 7 balls with 2 different backgrounds resulting a total of 14 video recorded trials in slow motion. In the trials, a member of the team dropped these balls individually as another member recorded the action with an iPhone 7 at 240 fps. During this process, the third member searched for additional clamps for the apparatus used to hold the iPhone 7. Several materials including steel, lead, wood, cork, rubber, and metal balls as well as a golf ball were dropped. The balls can be seen in Figure 1. Figure 1. The 7 Balls Figure 2 shows the iPhone 7 used along with the clamp to hold it securely to a horizontal metal stand. Figure 2 . iPhone 7 Holder and clamps  The first background was a wooden closet and the second background was a light blue brick wall. We used different backgrounds to see in which videos the visibility is best. Video 1 displays one of the seven recorded videos with a wooden closet background. Notice an error in the trial as...