What are the total distance the car travels and its displacement?
Find the displacement for each and add them. Let’s call north the positive direction, and south the negative direction. First, let’s convert minutes to seconds. 60 seconds in one minute, so: A car travels north at 30m/s for 600s. This means that every second, 30 meters are covered. Multiply 30 by 600: 18000 meters. It then travels south at 40m/s for 1200s. By the same principle, it travels 40 meters for every second. However, now it is traveling the opposite direction, so we multiply -40 by 1200 (time can’t be negative): -48000 meters. Now we add the two distances together. 18000 + (-)48000 = -30000. This is its displacement, and says that the car has traveled 30000 meters south. To find the total distance, take the absolute value of both distances (or just remove the negatives) and add them. 18000 + 48000 = 66000.
