The Physics
Opus in profectus


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  1. Suppose everyone in China was to jump in the air simultaneously. Estimate the following quantities to the nearest order of magnitude…
    1. the acceleration of the Earth
    2. the initial velocity of the Earth
    3. the maximum displacement of the Earth
  2. A surfer in a red wetsuit on a red, black, and white surfboard is riding a wave as shown in the diagram below. Draw a free body diagram showing the forces acting on…
    1. the surfer
    2. the surfboard

    Cartoon representation

  3. Write something.


  1. Write something.