1.7 Kinematics II

Pre-reading question: Imagine an object accelerates, and a camera takes a picture of the accelerating object once every second. Then, the camera puts all the images together. Draw what you think comes out of the camera.

Reading/Video: Take a look at this website:

Motion Diagrams

It explains how to make motion diagrams, which you need to know how to do for tomorrow.  Once you’ve read the site, click all the scenarios on the right side of the box in the top-middle. Take notes on this website, and try drawing a few of the diagrams along with the site. Save about a third (1/3) of your note taking space for the problem at the end of this post.

If you can’t get the website to work, or if you’re confused about what to click, look at this video:

 

Cops and Robbers:

The following is a famous physics problem.  One of the questions in the reading quiz tomorrow will be “How long did it take the police car to catch the speeder?”. Feel free to call and help each other, but if I find out anyone just gave an answer to someone else, both people will automatically fail tomorrow’s reading quiz.

The Problem: A speeder doing 40.0 mi/h (about 17.9 m/s) in a 25 mi/h zone approaches a parked police car. The instant the speeder passes the police car, the police begin their pursuit.  If the speeder maintains a constant velocity, and the police car accelerates with a constant acceleration of 4.51 m/s/s, (a) how long does it take for the police car to catch the speeder, (b) how far have the two cars traveled in this time, and (c) what is the velocity of the police car when it catches the speeder?

Interactive Video of the problem:

http://wps.aw.com/wps/media/objects/7123/7294233/interactive_figures/example2-9.html

Less interactive video of the problem:

Hint 1:

Hint 2:

Hint 3:

No after-reading question.

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