Question

a car travels 20 km north. it then turns around and travels 30 km south. what is the cars displacement? 50 km south 50 km north 10 km north 10 km south

Explanation:

Step1: Define directions

Let north be the positive - direction and south be the negative - direction.

Step2: Calculate displacement

The first displacement $d_1 = 20$ km (north, so $d_1= + 20$ km), and the second displacement $d_2=-30$ km (south). The total displacement $d=d_1 + d_2$. Substitute the values: $d=20+( - 30)=20 - 30=-10$ km. The negative sign indicates the direction is south.

Answer:

10 km south