Manic Monday Date: 12/10/07

1
Manic MondayDate 12/10/07

• You will need to have paper ready
• For the question to ponder that will consist of
  several multiple choice questions.

2
Q1

• The blue car weighs 100 Kg and the red car weighs
  150 Kg. Which car is doing the most work? How do
  you know?
• The blue car
• The red car
• Both have the same
• Cant tell, not enough information

3
Q2.

• The blue car weighs 100 Kg and the red car weighs
  150 Kg. It takes the cars 25 seconds to reach the
  end of the race. Which car has the most power?
  How do you know?
• The blue car
• The red car
• They have the same power
• Not enough information to tell

4
Q3.

• During your time on the stairs did you notice
  that usually the lightest person did the least
  work but had the most power.
• This is because light people dont work hard.
• This is because light people are very powerful
• This is because with work time doesnt matter but
  with power it does
• Cant be sure

5
Q4.

• Using the graph below, explain how force and
  acceleration are related. Is the same thing true
  for force and mass? Explain.
• F ma N
• F mg N

UNITS
6
notes

• You can use the question to ponder page and add
  these notes to it.

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Formulas, units, definition, and examples

• Work Force X Distance Power
  Work / time
• W F X d
  P W / t
• Unit Joule (J) Unit
  Watt (W)
• Work means a power means the
• change in position rate of change in
  work
• Examples include
  Examples include
• A car moving running up stairs
• A weightlifter jacking up a car to
• Lifting weights change a tire

8
Work example worked

• The brakes on a bicycle apply 120 N of frictional
  force to the wheels as the bicycle travels 10.0
  m. How much work have the brakes done on the
  bicycle?
• W F X d
• W 120 X 10
• W 1200 J

9
Power example worked

• Using a water hose, firemen do 5100 J of work to
  lift a car 5.00 m in 10.0 s. What is the
  firemens power output?
• P W / t
• P 5100 / 10
• P 510 W

10
Work and Power worksheet 1

• You may work with a partner to complete this
  worksheet by the end of class.
• I have updated grades to pass out and discuss
  with individuals so voice level must be a level 1.