A truck travels 90 m north then 30 m south then 40 m north what's the distance and displacement

The distance traveled by the truck is 160 m and the displacement of the truck is 100 m.

Explanation:

Distance is a scalar quantity while displacement is a vector quantity. So the scalar quantities are dependent only on the magnitude of that variable. While the vector quantities consider the direction along with the magnitude of variables. So distance covered by the truck is the measure of total distance traveled by the truck irrespective of path or direction. Thus the distance covered by the truck will be 90 m + 30 m + 40 m which is equal to 160 m.

While displacement is the vector addition of distance covered by the truck. So the direction is included in this measurement. As first the truck is going north, so S1 = 90 m, then as it turns to south which is completely opposite to north so S2 = - 30 m and then again it turns to north so, S3 = 40 m. Thus the displacement = S1+S2+S3=90-30+40 = 100 m.

So, distance is 160 m and displacement of truck is 100 m.