# 1C10.10 - Car on a Moving Sheet - Velocity Addition and Subtraction

Code Number:
1C10.10
Demo Title:
Car on a Moving Sheet - Velocity Addition and Subtraction
Condition:
Excellent
Principle:
Area of Study:
Mechanics
Equipment:
Toy cars with battery adapter for use with one or two batteries or the variable speed Pasco car, Cardboard or Masonite sheet, Suction Cups.
Procedure:

See the 1H10.20 and 1J30.60 entries also.

Place the Pasco car running at the desired velocity onto the Masonite sheet.  Move the sheet with the car direction for velocity addition and against the car direction for velocity subtraction.

Take out the battery adapter and add the second battery to make the car go with twice the velocity.

Take the two bolts and with a head of a bolt in each hand place and match the threads together.  Now as you orbit one bolts threads around the other bolts threads, the bolts will stay in exactly the same place, not screwing either together or away from each other.

References:
• Nuno M. Campos, Pedro Silva, Sergio R. Domingos, Manuela Ramos Silva, "Relative Motion Made Real", TPT, Vol. 61, #6, Sept. 2023, p. 534.
• James Lincoln, "Way Too Many Demos with the Constant Velocity Car", TPT, Vol. 60, #8, Nov. 2022, p. 710.
• Christopher Chiaverina, "The Versatile Constant Velocity Car", TPT, Vol. 58, #7, Oct. 2020, p. 524.
• David L. Cone, "Floating in Real Rivers", TPT, Vol. 36, #6, Sept. 1998, p. 323.
• Paul Hewitt, "Figuring Physics", TPT, Vol. 36, #4, Apr. 1998, p. 240
• James F. Jackson, "Real Rivers / Ideal Streams", TPT, Vol. 37, #1, Jan. 1999, p. 3.
• Gamze Sezgin Selcuk and Kemal Yurumezoglu, "Perception of Relative Motion Between Two Systems Through the Sense of Touch: The Example of the Moving Walkway", TPT, Vol. 51, #9, Dec. 2013, p. 549.
• Julius Sumner Miller, Q25 & A25, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 26 & 84.
• Julius Sumner Miller, Q28 & A28, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 28 & 86.
• Julius Sumner Miller, Q33 & A33, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 31 & 87.
• Julius Sumner Miller, Q132 & A132, Millergrams II – Some More Enchanting Questions for Enquiring Minds, p. 21 & 83.

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