depth study help (1 Viewer)

[kkk579]

When I was using the Video Physics app, which requires me to plot points of the balls movement during every frame I conducted the experiment in my house where it was not extremely bright, plus I used the school's ipad which is relatively old so it doesn't have the best quality camera which resulted in a massive blur so I couldn't really tell where the ball was so I just had to place the point in the middle of every blur.

However I did account for this blur by taking the measurements of uncertainties in the displacement. But since these were only approximations it probably isn't EXTREMELY accurate

So would this be a systematic or random error? Because the amounts of blur at every point of the ball's motion was different, as the ball kept getting closer to the ground the blur got larger since its velocity increased. The amount of blur varied between trials too. My experiment is just verifying whether drag force affects motion btw.

 

[kkk579]

Also would anyone be able to read over mine?

 

[kkk579]

bump

 

[wizzkids]

Since you are making a video then you must obtain the frame rate from the metadata in the video file.
The frame rate might vary between experiments. Do you know the frame rate?
The blur in the position of the ball is caused by the shutter speed of the camera. If the shutter speed of the camera is 1/25 sec then the time for each frame will be 40 milliseconds, and that is enough to cause quite a lot of blur.
What you should do is consistently estimate the position of the ball when the shutter opened, i.e. at the back of the blurred image. Do not use the middle point of the blurred image, because that will not represent equal time intervals.
If you can estimate the back edge of each image and do that consistently and reliably then you should be able to compensate for the slow shutter speed.

 

[kkk579]

Since you are making a video then you must obtain the frame rate from the metadata in the video file.
The frame rate might vary between experiments. Do you know the frame rate?
The blur in the position of the ball is caused by the shutter speed of the camera. If the shutter speed of the camera is 1/25 sec then the time for each frame will be 40 milliseconds, and that is enough to cause quite a lot of blur.
What you should do is consistently estimate the position of the ball when the shutter opened, i.e. at the back of the blurred image. Do not use the middle point of the blurred image, because that will not represent equal time intervals.
If you can estimate the back edge of each image and do that consistently and reliably then you should be able to compensate for the slow shutter speed.

My physics teacher told me to use the middle

 

[wizzkids]

My physics teacher told me to use the middle

Well, I disagree. However, you must follow what your teacher wants because he/she is going to mark the work.