Physics 211 Lec 11: Newtons Laws in Circular Motion

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Physics 211 Lec 11 Newtons Laws in Circular
Motion

• Recall Newtons Second Law

• Recall radial acceleration

• So, for centripetal force we now have

• Now recall total acceleration for non-uniform
  circular motion

where

• So, for total circular motion force we now have

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Example Ch6 5Coin 30cm from center of rotating
horizontal turntable slips at speed of 50cm/s.a)
what force causes the centripetal acceleration
for no slip conditionb) Find ?s between coin and
table
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Example Ch6 1585kg Tarzan swings on 10m vine
of tensile strength 1000N to cross river with
speed of 8m/s at bottom. Will the vine break?
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Questions for Groups

• 6.4 Describe path of moving body w/ constant
  magnitude of accel and
• Acceleration perpendicular to velocity
• Acceleration parallel to velocity
• 6.6 Why is the earth non-spherical with a bulge
  at the equator?
• 6.10 Potential space colonies might consist of
  5mi diameter 10mi length rotating cylinders. How
  would these colonies effectively simulate the
  earths gravity?