Mr. Simple
Ashraf El-messidi, Chris Kilby,
Travis Pearce, & Clayton Thomas
Overview
This device performs several steps to
complete the simple task of displaying a
banner. A hammer swings from its resting
position to hit a marble. This ball rolls down
multiple ramps, changing direction along the
way. Finally the ball hits a car, which rolls
down a track, displaying our banner.
Concepts
• Conservation of Translational Energy
– Ball falling and rolls
• Conservation of Rotational Energy
– Rotating hammer hits ball at rest
• Conservation of Linear Momentum
– Ball hits car
• Rotational Motion
– Hammer Swinging
• Center of Mass
– Car rest with over half of body over the edge
Calculations
• Velocity of hammer
– Gh=.5v^2 + .5Iw^2
• V=11 ft/sec = 29.3 radians/sec
• Initial Velocity of ball
– m1v1+m2v2=m1v1’+m2v2’
• V of ball=12.36 ft/sec
• Other calculations could not be performed
because the coefficient of restitution could
not be found for the ball hitting the car
Cost/Conclusion
• Nothing was purchased. The following is a list of
estimated cost.
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–
–
–
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Toy car: $2
Scrap wood: $4
Marble: $1
Paper, string, cardboard, and other small items: $2
Most expensive purchase was a 4 pack of sharpies that
included the orange sharpie we needed. This was $6
• Total Cost: $15
• This was the most effective, consistent, and cost
efficient design we could build.
Thanks