挑戰一:某連隊等速直線前進,部隊全長 600m,傳令兵自隊尾等速跑到隊首遞交報告給連長後,
立刻以原速率跑回隊尾,此時整個連隊恰好前進了800m,則全程傳令兵移動的路徑長為?/boom
# A popular web video shows a jet airplane, a car, and a motorcycle racing from rest
along a runway. Initially the motorcycle takes the lead, but then the jet takes the lead,
and finally the car blows past the motorcycle. Here let's focus on the car and motorcycle
and assign some reasonable values to the motion. The motorcycle first takes the lead because
its (constant) acceleration am 8.40 m/s² is greater than the car's (constant)
acceleration ac 5.60 m/s², but it soon loses to the car because it reaches its greatest
58.8 m/s before the car reaches its greatest speed 106 m/s. How long does
speed
the car take to reach the motorcycle? 16.6