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By: Tyler Harris Today we started the class by getting back the reading guides. Then we did a daily question. The guests at a large table in a Chinese restaurant use a revolving tray to share the food dishes. How does the revolving tray’s motion differ from that of the passing desert cart?

The desert cart is being pushed in a straight line, but the revolving tray stays stationary and revolves around a certain point. The rotating tray also only has one axes of rotation and the cart has four.

The next thing we did was complete a problem and take notes (the notes are also on page Three)

The problem was to find the tangential velocity of Mr. Manning’s Ferris wheel.

Tangential Velocity: the object on the outside of the circle is moving in an exact tangent to the circle

V=Circumference/Tine (for one rotation) =(2(Pi)r)/Time =(2(Pi).357)/13.79 V=.1626m/s If the motion of what you are measuring is too fast to time by hand, we can find the frequency

F=(# of rotations)/(Time)=(4 rot.)/(1 min.)=(4 rot.)/(60 sec.)= 1/15 r/s = .067r/s

To find the time for one rotation (period): T= 1/F = 1/.067 = 15s ß The fifteen seconds should always be almost exactly to the time you got in the velocity equation

We went on to complete another problem about a ride at Hershey park named the claw.

Frequency of claw: 9rev/min Radius: 6 meters F= 9/60 = .15r/s T= 1/F = 1/.15 = 6.67 s Tangential speed= 37.7m/6.67s = 5.7

Then we worked on practice problems for the rest of the period. The homework is page four