Phy 2049: Physics II

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Phy 2049 Physics II

• Syllabus, grades and exams
• Electricity, Magnetism, optics
• Electricity
• Charge
• Force
• Constants

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Phy 2049 Physics II

• Coulombs Law
• F in Newtons, r in meter, q in Coulomb and k is
  the fix.
• F is a vector, directed along a line joining the
  charges.
• The force can be added like a vector

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Phy 2049 Physics II

• Two equally charged particles are held 2.5X
  10-3 m apart and then released from rest. The
  initial acceleration of the first particle is
  observed to be 5.0 m/s2 and that of the second to
  be 11.0 m/s2. The mass of the first particle is
  6.3X10-7 kg.
• What is the mass of the second particle?
  2.86e-07 kg
• What is the magnitude of the charge of each
  particle? 4.68e-11 C

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Phy 2049 Physics II

• Two equally charged particles are held 2.5X
  10-3 m apart and then released from rest. The
  initial acceleration of the first particle is
  observed to be 5.0 m/s2 and that of the second to
  be 11.0 m/s2. The mass of the first particle is
  6.3X10-7 kg.
• What is the mass of the second particle?
• What is the magnitude of the charge of each
  particle?

• M1a1 M2a2 F kq2/r2
• M2 M1a1/a2 2.86x10-7 kg
• q2 r2 M1a1/k
• q 4.68x10-11 C

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Phy 2049 Physics II

• In Fig. 21-22, the particles have charges q1
  -q2 298 nC and q3 -q4 280 nC, and distance
  a 4.0 cm.
• What are the a) x 0.607 N and b) y -0.303 N
  components of the net electrostatic force on
  particle 3?

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Phy 2049 Homework

• Because the summer semester is quite short, the
  homework assignments are rather large. I would
  suggest that you do as many as you can at the
  earliest chance possible. I would certainly urge
  you not to try them all the night before they are
  due.

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Phy 2049 Homework

• Visit Webassign (http//www.webassign.net)
• Physics is a little like riding bicycle. No one
  has learned how to ride a bicycle by reading an
  owners manual.
• It is very hard in the beginning, but then it
  becomes instinctive. That is when you start to
  enjoy the scenery
• Try doing homework in a group.

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Phy 2049 Homework

• Coulombs law
• Addition of forces as vectors