Question
A 17-car train standing on the siding is started
in motion by the train’s engine. 4 cm slack is
between each of the cars, which are 9 m long.
The engine is tightly connected to the first car
and moves at a constant speed of 25 cm/s.
How much time is required for the pulse to
travel the length of the train?
in motion by the train’s engine. 4 cm slack is
between each of the cars, which are 9 m long.
The engine is tightly connected to the first car
and moves at a constant speed of 25 cm/s.
How much time is required for the pulse to
travel the length of the train?
Answers
oobleck
well, the total slack is 16*4cm = 64cm
so, as the slack is reduced by 25 cm/s, and time = distance/speed, ...
The length of each car does not matter, unless there is some stretch constant telling how long it takes for the pulse to move the length of the car.
so, as the slack is reduced by 25 cm/s, and time = distance/speed, ...
The length of each car does not matter, unless there is some stretch constant telling how long it takes for the pulse to move the length of the car.