In: Physics
A car travels along a straight east-west road. A coordinate system is established on the road, with x increasing to the east. The car ends up 19 mi west of the intersection with Mulberry Road.
(A) If its displacement was -21 mi , how far from Mulberry Road did it start?
Let us imagine the East-West road as x-axis, and the point of intersection of Mulberry road is at x = 0. This implies that, the west of the intersection is -ve and the east side will be represented +ve.
Given the car ends up at 19 mi West to the intersection, implies that it ends at -19 mi from x = 0. Also given the total displacement = -21 mi.
We know that displacement = final position - initial position
Hence, initial position = final position - displacement
= -19 - (-21)
= -19 + 21
= 2 mi.
So, the car started from 2 mi from the Mulberry road and from the East of it.