Announcements

1
Announcements

• New homework (Ch. 6, Probs 45 58)
• Office hours
• M 1-2 pm
• TWF 3-4 pm
• R 10-11 am
• Tutorial Learning Center - Houston Hall 120/110
• M 8-10 am, 11-noon, 1-7 pm R 9-1 pm, 2-7 pm,
  7-9 pm
• T 9-noon, 1-7 pm, 7-9 pm F 8-1 pm, 2-5 pm
• W 8-9 am, 11-noon, 2-7 pm, 7-9 pm (Grand
  Mesa Hall)

2
Chapter 6

• Momentum and Collisions
• (Problem Session)

3
Serway 6.50

• Two automobiles of equal mass approach an
  intersection. One vehicle is traveling with
  velocity 13.0 m/s toward the east, the other is
  traveling north with speed v2i. Neither driver
  sees the other. The vehicles collide in the
  intersection and stick together, leaving parallel
  skid marks at an angle of 55.0º north of east.
  The speed limit for both roads is 35 mi/h, an the
  driver of the northward-moving vehicle claims he
  was within the limit when the collision occurred.
• Is he telling the truth?

4
Serway 6.21

• High-speed stroboscopic photographs show that
  the head of a 200-g golf club is traveling at 55
  m/s just before it strikes a 46-g golf ball at
  rest on a tee. After the collision, the club
  head travels (in the same direction) at 40 m/s.
• Find the speed of the golf ball just after the
  impact.

5
Serway 6.16

• A pitcher throws a 0.15-kg baseball so that it
  crosses home plate horizontally with a speed of
  20 m/s. The ball is hit straight back at the
  pitcher with a final speed of 22 m/s.
• What is the impulse delivered to the ball?
• Find the average force exerted by the bat on the
  ball if the two are in contact for 2.0 x 10-3 s.