a) The distance travelled by the the locomotive is 30 meters, b) The final displacement of the locomotive is 6 meters westwards.
Explanation:
a) The distance travelled is the sum of magnitudes of distances covered by the train during its motion. That is to say:
The distance travelled by the the locomotive is 30 meters.
b) The displacement is the vectorial distance of the train with respect to a point of reference, since west and east are antiparallel to each other, calculations can be simplified to a scalar form. Let suppose that movement to the east is positive. The calculations are presented below:
The final displacement of the locomotive is 6 meters westwards.
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