A drone flies 35 km South, then 27 km East, then 20 km North, then 19 km West. Calculate the magnitude of its displacement from the launch point.

Important Notes

• Separate total path length from displacement; the question asks for the straight-line gap between start and finish. |
• Use East = +x, West = −x, North = +y and South = −y. |
• A route may be long while its displacement is small, so never add every segment unless total distance is requested. |
• Estimate the answer before selecting an option: the displacement must be less than or equal to the route length. |