Worked Example 01
The Question
(slightly modified from exam question)
The Australian Federal Police have asked for your help. A prominent politician was recently walking past a block of apartments in Civic when they were narrowly missed by a falling flower pot. They believe that this was an assassination attempt. Nobody saw who dropped the flowerpot, or where it came from. It could have been dropped off the balcony of any of the apartments above. The impact of the flowerpot was, however, caught on a security camera. Your job is to use your knowledge of science to work out how fast the flowerpot was moving, and from how high it was dropped. The police will then interview the people who live on the appropriate floor of the apartment block.
The flowerpot is clearly visible in two consecutive frames from the security camera. The camera takes 20 ± 0.1 frames per second. In the first frame, you estimate that the pot is 1.2 m ± 2cm above the pavement, while in the second frame the height is 16 ± 2cm.
The Answer
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