1. MiniDrillHomework

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1. Mini-Drill/Homework

• Problem 32, page 51 A jet plane lands with a
  speed of 100 m/s and can accelerate at a maximum
  rate of -5.00 m/s2 as it comes to rest. (a) From
  the instant the plane touches the runway, what is
  the minimum time needed before it can come to
  rest? (b) Can this plane land on a small tropical
  island airport where the runway is 0.800 km long?

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Solution Mini-Drill 1 part(a)
y
x
vxf 0
vxo 100 m/s
ax -5.00 m/s2
xf ?
xi 0
t ?
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Solution Mini-Drill 1 Part(a)
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Solution Mini-Drill 1 Part(b)
In 20.0 s the jet travels
Runway is too small
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2. Mini-Drill/Homework

• Determine Justin Gatlins average speed during
  the100 m sprint finals in the Olympics. Put the
  answer in units of m/s, and then convert the
  units to mph.

From the video, we saw that it took 9.85 s for
Justin to win the race.