Exploration 1: The Pole and Barn "Paradox"

From the Frame of the Barn From the Frame of the Pole

Please wait for the animation to completely load.

A pole vaulter carries her pole towards a barn as shown in the animation (position is given in meters and time is given in meters).  The pole is seen to be 10-m long when it is moving as seen from the frame of the barn.  Also shown above the barn is the spacetime diagram depicting the pole and the barn from two frames of reference: the pole and the barn.  When an object is stationary in a reference frame it is red and when it is moving it is green.  Restart

Select From the Frame of the Barn and play. 

  1. How fast is the pole moving relative to the barn (measured in c)? 

  2. What is 1/slope of the red and green worldlines, respectively?

  3. What do events A, B, A', and B' refer to?  Which if any of these events are simultaneous in this reference frame?

Select From the Frame of the Pole and play. 

  1. How fast is the barn moving relative to the pole (measured in c)? 

  2. How long is the pole in this reference frame?  Why is it this long?

  3. How long is the barn in this reference frame?  Why is it this long?

  4. What do events A, B, A', and B' refer to?  Which if any of these events are simultaneous in this reference frame?

 

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