Momentum

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Momentum
Image http//insidethecosmiccube.blogspot.com/200
8/01/whats-story-mourning-glory.html
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Vocabulary Sheets Due
Sept. 24
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Monday

• Sept. 8

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Momentum

• p mv

p momentum (kgm/s) m mass (kilograms,
kg) v velocity (meters/second, m/s)
Momentum amount of motion
Example A superhero of mass 75 kg is moving at
65 m/s. Find the momentum of our man in
tights. Find the velocity at which a freight
train of mass 200,000 kg has the same momentum.
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Impulse

• I F?t

I impulse F force (Newtons, N) ?t change in
time (seconds, s)
Thanks Mr. Newton
Impulse is change in momentum
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As Seen in Action Comics 13

• Superman stops a locomotive.
• A 200,000kg train is moving at 15 m/s. After
  Superman flies into it, the train is moving at 0
  m/s.
• What impulse did Superman deliver to the train?
• If Superman and the train were in contact for 2
  seconds, what average force did he exert?
• What was the average acceleration of the train
  during its contact with Superman?

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Classwork

• Page 193
• Problems 2-6

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Tuesday

• Sept. 9

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Energy Super Heroes

• Projects due September 24
• You must work at home on these. Theres not
  enough class time.
• This week
• 1. Super power
• 2. Name origin story
• 3. List of concepts your hero can demonstrate.

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Energy Super Heroes
Presentations start on Sept. 24
Format Slide show speech Video Poster
presentation Others?
Image http//www.coverbrowser.com/covers/action-c
omics
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Rubric Super Hero ProjectWeek 2
Objective Value
Hero is original 25
Super power relevant to our topic 25
Hero has a name and identity 25
List of concepts your hero can demonstrate (ie, what physics will you be showing?) 25
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Superhero Energy Project

• Due Monday, September 15 by email or hard copy in
  class.
• From kinetic energy, potential energy, and
  conservation of energy, write 1 problem at
  minimum.
• From thermal energy, thermodynamics, and specific
  heat, write 1 problem at minimum.
• From momentum, impulse, and conservation of
  momentum, write 1 problem at minimum.
• Looking forward and due on Friday, Sept. 19 From
  any of the above topics, write 2 additional
  problems.

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Friday

• Sept. 12

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How Fast

• v2 2gh

Velocity squared equals two times acceleration
due to gravity times height
Note How fast doesnt care how heavy.
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Impulse

• I F?t

I impulse F force (Newtons, N) ?t change in
time (seconds, s)
Thanks Mr. Newton
Impulse is change in momentum
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Terminal Velocity

• The upper limit of how fast.

How fast? Skydiver with a semi-closed parachute
195 km/h (120 mph) World record human freefall
speed is 988 km/h (614 mph)
How long? About 15 seconds
It happens when your weight is exactly balanced
by an upward force called drag.
Source http//en.wikipedia.org/wiki/Terminal_velo
city
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