PHYS 2101

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PHYS 2101
Spring 2009

• Week One Revisited
• Newtons Laws
• Kinematics
• 1-dimensional
• 2-dimensional
• Graphical

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PHYS 2101
Fall 2008
A block of mass m1 rests on a rough inclined
plane and is attached to a hanging mass of mass
m2 by a string which is draped over a
frictionless, massless pulley. If ?k0.1, ?15º,
and m12m2, what is the magnitude and direction
of the acceleration of the hanging mass?
EX1
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PHYS 2101
Spring 2009
EX2
If the ramp is 1.2 m long and m1 starts from rest
at the bottom of the ramp, how long does it take
m1 to reach the top of the ramp?
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PHYS 2101
Spring 2009
position (m)
time (s)
velocity (m/s)
time (s)
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PHYS 2101
Spring 2009
EX3
A small child of mass 31 kg swings back and forth
on a rope swing whose length is 3.8 m. At the
bottom of each swing (i.e., when the rope is
vertical), her speed is 4.2 m/s. What is the
magnitude of the tension in the rope at the
instant when she is at the bottom of each swing?