Relative Motion / Frames of Reference




Things to remember from tonight's class demonstrations.


https://youtu.be/lbGCa5EPZhQ

Thanks, Amanda!

- the ball shot from the cart lands in the cart, because it was moving at the same speed as the cart.  This is similar to Galileo's ship problem, or the idea of apples falling near the base of the apple tree.


Now some data processing:



The blue dots highlight the actual path of the ball - a parabola!





This graph is a little confusing, since it shows 2 different motions.  The red dots are the horizontal position of the ball - continually moving forward at a constant speed (which is the same as the car).  The blue dots show the ball rising and then falling, due to gravity.  These 2 motions combine to make the mathematical curve called a parabola.






- the ball released from the top of the hook (on the cart) still lands in the cart itself, for the same reason:  ball is moving at the same speed as the cart.

https://youtu.be/ZzzFlzoGg68

 Again, thanks to Amanda for filming.
Data processing part 2:


Descriptions are the same as above.

Physics - Yay!!!

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