SAT physics question

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1

<p>Two identical, human looking robots are standing and facing forward in separate spaceships. Both ships are moving at 0.8c but are travelling in opposite directions, as shown above. (apologies for not being able to provide diagram, you can find the exact question with diagram here: <a href=“http://ttlearning.com/wp-content/uploads/2013/05/Magazine_May2013-web-eng.pdf”>http://ttlearning.com/wp-content/uploads/2013/05/Magazine_May2013-web-eng.pdf&lt;/a&gt;) If a person on the spaceship with robot A could make measurements on both robots, which of the following would the person observe to be different.
A) the robots’ heights
B) the length of the robots’ feet from toe to heel
C) the width of the robots’ faces
D) The length of the robot’s legs
E) the width of the robot’s shoulders</p>

<p>Please help?</p>

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<p>B. It is the only dimension moving towards the observing robot. It will appear to be shorter. All the other dimensions remain the same. Of course, if the robot lies down head towards the observer, A, and D are correct. If the robot turns sideways to the observer, C and E are correct.</p>