BCC g Project

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...

Today the group continued with experimentation by using a video analysis program called Pasco Capstone to determine the experimental acceleration value of gravity. Procedures to use Pasco Capstone for the experiment include: adjusting the scale, setting the frame rate to 240 fps, and to have each click with the mouse on the object to move 5 frames. This way, each point plotted in the video corresponds to a displacement and a time. From there on, steps were taken to create a graph of both displacement vs. time and velocity vs. time to get the acceleration due to gravity. In trials including a golf ball, steel ball, and wooden ball using both iPhone and Samsung cameras, the group found that the steel ball showed the most accurate value for acceleration due to gravity, 9.79 +/- 0.09 m/ s 2   while g for the golf ball was 9.41 +/1 0.10 m/ s 2 .  This may be evidence that air resistance plays a part in the general error presented during the experimentation. Overall, the...

Project Name: BCC G Project Time: 1pm to 3 pm Today, we started with the initial trials for the new free-fall experiment setting up the experiment apparatus and shooting the video through different cell phone cameras. First off, we collected a few items that can be dropped from a height slightly higher than 2 meters. We found a golf ball, a wooden ball and a small steel ball. In figure 1, you can see the slow motion video of the first trial taken using iPhone 7 with 720p and 240fps of the golf ball dropped from above the door height. Figure 2 shows the second trial taken using Samsung Galaxy S7 Edge with the same quality. We thought it was important to try taking the slow-motion video in different cell-phones because we were checking to see if it was feasible for students to take their own videos in class to perform the experiment. Now, we're going to try to use different apps and software such as PASCO that will allow the students to analyze the video and find mea...

Project name (temporary): BCC g Project Mentor:  Dr. Estelle Epstein Student Interns:  Jennifer Mikulko, Shivani Patel, Jan Mark Talingdan Scheduled Meeting times:  M-Th 1 - 3 PM in Room S-332 Objectives:  To create a  new experiment for first semester Physics courses to calculate g by plotting v  vs t  of a falling object derived from a slow motion cellphone video.  This will be written up in a manner that can be executed by a first semester Physics student.