Anna and Bob have identical spaceships 60 m long. The diagram shows Bob’s observations of Anna’s ship, which passes at a speed of
(a) What does this clock read?
(b) Later, the back of Anna’s ship passes Bob. At what time does this occur according to Bob?
(c) What will observes in Bob’s frame see on Anna’s two clocks at this time?
(d) Identify two events that show time dilation and two that show length contraction according to Anna.
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