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Kamal starts from Point A and drives 17 km towards south. He then takes a left turn, drives 13 km, turns left and drives 21 km. He then takes a left turn and drives 18 km. He takes a final left turn, drives 4 km and stops at Point P. How far (shortest distance) and towards which direction should he drive in order to reach Point A again? (All turns are 90┬░ turns only unless specified.)
3 km to the east
5 km to the east
4 km to the east
6 km to the east
5 km to the east
Track net displacements along North-South and East-West axes independently. Net NS movement = +17 - 21 + 4 = 0 km. Net EW movement = -13 - 18 = -31 km from start? Let's check step-by-step.
Starting point A = (0, 21), moves 17 km South, 13 km West, 21 km North, 18 km West, and 4 km South to Point P.
d=(x2тАЛтИТx1тАЛ)2+(y2тАЛтИТy1тАЛ)2тАЛ
Track net displacements along North-South and East-West axes independently. Net NS movement = +17 - 21 + 4 = 0 km. Net EW movement = -13 - 18 = -31 km from start? Let's check step-by-step.
Confusing left and right turns relative to the current heading, or miscalculating the net coordinates relative to Point A.
Step 1: Set up Coordinate System
Let Point A be the origin (0,0) on a Cartesian plane where North is +y, South is тИТy, East is +x, and West is тИТx.
A=(0,0)r
Step 2: Trace Movements
P=(тИТ5,0)r
Step 3: Calculate Distance and Direction to A
Point P is at (тИТ5,0) and Point A is at (0,0). To reach A from P, Kamal needs to move 5┬аkm along the positive x-axis, which corresponds to the East direction.
Distance=5┬аkm,Direction=East
Option B is correct because Kamal ends up at Point P, which is 5 km west of Point A, meaning he must travel 5 km to the east to reach Point A again.
Direction problems can always be modeled as vector addition or coordinate movements to avoid visual errors.